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PurposeThis study was a quality-control study of resting and exercise Doppler echocardiography (EDE) variables measured by 19 echocardiography laboratories with proven experience participating in the RIGHT Heart International NETwork.MethodsAll participating investigators reported the requested variables from ten randomly selected exercise stress tests. Intraclass correlation coefficients (ICC) were calculated to evaluate the inter-observer agreement with the core laboratory. Inter-observer variability of resting and peak exercise tricuspid regurgitation velocity (TRV), right ventricular outflow tract acceleration time (RVOT Act), tricuspid annular plane systolic excursion (TAPSE), tissue Doppler tricuspid lateral annular systolic velocity (S’), right ventricular fractional area change (RV FAC), left ventricular outflow tract velocity time integral (LVOT VTI), mitral inflow pulsed wave Doppler velocity (E), diastolic mitral annular velocity by TDI (e’) and left ventricular ejection fraction (LVEF) were measured.ResultsThe accuracy of 19 investigators for all variables ranged from 99.7 to 100%. ICC was > 0.90 for all observers. Inter-observer variability for resting and exercise variables was for TRV = 3.8 to 2.4%, E = 5.7 to 8.3%, e’ = 6 to 6.5%, RVOT Act = 9.7 to 12, LVOT VTI = 7.4 to 9.6%, S’ = 2.9 to 2.9% and TAPSE = 5.3 to 8%. Moderate inter-observer variability was found for resting and peak exercise RV FAC (15 to 16%). LVEF revealed lower resting and peak exercise variability of 7.6 and 9%.ConclusionsWhen performed in expert centers EDE is a reproducible tool for the assessment of the right heart and the pulmonary circulation.

Objective We sought to determine if decreased left ventricular systolic function was associated with an increased risk of postoperative infectious, respiratory, or renal complications in patients undergoing noncardiac surgery. Design Retrospective cohort study. Setting Single tertiary-care, university-based medical center. Patients We studied individuals who participated in the American College of Surgeons National Quality Improvement Program and had a preoperative echocardiogram conducted at our institution. Interventions None. Measurements The incidences of postoperative respiratory (need for postoperative mechanical ventilation or unplanned intubation), renal (acute renal failure or renal insufficiency), and infectious (pneumonia, urinary tract infection, sepsis, or wound infection) complications were analyzed. Main results Postoperative infections (n=175, 10%) represented the most common postoperative complication seen in the study population of 1692 individuals. Respiratory complications occurred in 77 (5%) and renal complications occurred in 29 (2%) participants. The time between the echocardiogram and surgery ranged from 7 months (interquartile range [IQR] 1.8-15.7) for those with severely reduced left ventricular ejection fraction (LVEF) to 24 months (IQR 2.5-38.6) for those with a normal LVEF ( P =.038). Univariate analysis demonstrated a relationship between decreased preoperative LVEF and infectious and renal complications, but not respiratory complications. After adjusting for preoperative characteristics, decreased preoperative LVEF was associated with infectious (odds ratio, 1.33; 95% confidence interval, 1.03-1.68; P =.0265) and renal (odds ratio, 1.69; 95% confidence interval, 1.12-2.48; P =.0142) complications. Conclusions Decreased preoperative LVEF is associated with postoperative infections and renal complications.

Transesophageal echocardiography (TEE) is the standard for evaluating cardioembolic sources of stroke, although many strokes remain cryptogenic after TEE. Cardiac magnetic resonance (CMR) imaging may have advantages over TEE. We performed a prospective pilot study comparing CMR to TEE after stroke to assist in planning future definitive studies.Individuals with nonlacunar stroke within 90 days of undergoing clinical TEE were prospectively identified and underwent a 1.5 Tesla research CMR scan. Exclusion criteria included50% relevant cervical vessel stenosis and inability to undergo nonsedated CMR. A descriptive comparison of cardioembolic source (intracardiac thrombus/mass, aortic atheroma ≥ 4 mm, or patent foramen ovale [PFO]) by study type was performed.Twenty patients underwent CMR and TEE a median of 6 days apart. The median age was 51 years (interquartile range [IQR] 40, 63.5), 40% had hypertension, 15% had diabetes, 25% had a previous stroke/transient ischemic attack, 5% had atrial fibrillation, and none had coronary disease or heart failure. No patient had intracardiac thrombus or mass detected on either study. Aortic atheroma ≥ 4 mm thick was identified by TEE in 1 patient. CMR identified aortic atheroma as4 mm in this patient (3 mm on CMR compared with 5 mm on TEE). PFO was identified in 6 of 20 patients on TEE; CMR found only 1 of these.In this pilot study, TEE identified more potential cardioembolic sources than CMR imaging. Future studies comparing TEE and CMR after stroke should focus on older subjects at higher risk for cardiac disease to determine whether TEE, CMR, or both can best elucidate potential cardioembolic sources.

Patients with frequent premature ventricular complexes (PVCs) are at risk of developing reversible PVC-induced cardiomyopathy (rPVC-CMP). Not all determinants of rPVC-CMP are known.To assess the impact of the QRS duration of PVCs on the development of rPVC-CMP.In a consecutive series of 294 patients with frequent idiopathic PVCs referred for PVC ablation, the width of the PVC-QRS complex was assessed. The QRS width was correlated with the presence of rPVC-CMP.The PVC-QRS width was significantly greater in patients with rPVC-CMP than in patients without rPVC-CMP (164 ± 20 ms vs 149 ± 17 ms; P.0001). The site of origin of the PVC had an impact on the PVC-QRS width, with epicardial PVCs having the broadest QRS complexes. Patients with PVCs originating from the right ventricular outflow tract or the fascicles had the narrowest QRS complexes. After adjusting for PVC burden, symptom duration, and PVC site of origin, PVC-QRS width and an epicardial PVC origin were independently associated with rPVC-CMP. Based on receiver operator characteristics analysis, a QRS duration of150 ms best differentiated patients with and without rPVC-CMP (area under the curve 0.66; sensitivity 80%; specificity 52%). The PVC burden for developing rPVC-CMP is significantly lower in patients with a PVC-QRS width of ≥150 ms than in patients with a narrower PVC-QRS complex (22% ± 13% vs 28% ± 12%; P.0001).Broader PVCs and an epicardial PVC origin are associated with the development of rPVC-CMP independent of the PVC burden.

Frequent premature ventricular complexes (PVCs) can cause cardiomyopathy. The mechanism is not known and may be multifactorial.This study assessed the role of PVC interpolation in PVC-induced cardiomyopathy.In 51 consecutive patients (14 women, age 49 ± 15 years, ejection fraction (EF) 0.49 ± 0.14) with frequent PVCs, 24-hour Holter recordings were performed. The amount of interpolation was determined and correlated with the presence of PVC-induced cardiomyopathy. In addition, parameters measured during an electrophysiology study were correlated with the Holter findings.Fourteen of the 21 patients (67%) with cardiomyopathy had interpolated PVCs, compared with only 6 of 30 patients (20%) without PVC-induced cardiomyopathy (P.001). Patients with interpolated PVCs had a higher PVC burden than patients without interpolation (28% ± 12% vs. 15% ± 15%; P = .002). The burden of interpolated PVCs correlated with the presence of PVC cardiomyopathy (21% ± 30% vs. 4% ± 13%; P = .008). Both PVC burden and interpolation independently predicted PVC-induced cardiomyopathy (odds ratio 1.07, 95% confidence interval 1.01 to 1.13, P = .02; and odds ratio 4.43, 95% confidence interval 1.06 to 18.48, P = .04, respectively). The presence of ventriculoatrial block at a ventricular pacing cycle length of 600 ms correlated with the presence of interpolation (P = .004). Patients with interpolation had a longer mean ventriculoatrial block cycle length than patients without interpolated PVCs (520 ± 110 ms vs. 394 ± 92 ms; P = .01).The presence of interpolated PVCs was predictive of the presence of PVC cardiomyopathy. Interpolation may play an important role in the generation of PVC-induced cardiomyopathy.

Frequent idiopathic premature ventricular complexes (PVC) are associated with a reversible form of cardiomyopathy. The effect of frequent PVCs on left ventricular function has not been evaluated in post-infarction patients.This study sought to evaluate the value of post-infarction PVC ablation and possible determinants of a reversible cardiomyopathy.Thirty consecutive patients (24 men, age 61 +/- 12, left ventricular ejection fraction [LVEF] 0.36 +/- 0.12) with remote myocardial infarction referred for implantable cardioverter-defibrillator (ICD) implantation for primary prevention of sudden death or for management of symptomatic ventricular tachycardia or PVCs were evaluated. Fifteen patients with a high PVC burden (or=5% of all QRS complexes on 24-h Holter monitor) underwent mapping and ablation of PVCs before ICD implantation. The remaining 15 patients served as a control group. LVEF was assessed by echocardiography, and scar burden was assessed by cardiac magnetic resonance imaging with delayed enhancement (DE-MRI) in both groups.PVC ablation was successful in 15 of 15 patients and reduced the mean PVC burden from 22 +/- 12% to 2.6 +/- 5.0% (P.001). After the procedure, LVEF increased significantly from 0.38 +/- 0.11 to 0.51 +/- 0.09 in the PVC ablation group (P = .0001). In the control group, LVEF remained unchanged within the same time frame (0.34 +/- 0.14 vs. 0.33 +/- 0.15; P = .6). Patients with frequent PVCs had a significantly smaller scar burden by DE-MRI compared with control patients. Five of the patients with frequent PVCs underwent ICD implantation.Post-infarction patients with frequent PVCs may have a reversible form of cardiomyopathy. DE-MRI may identify patients in whom the LVEF may improve after ablation of frequent PVCs.

59-year-old man presented with a 6-month history ofexertionaldyspnea.Hereportednochestpain,palpita-tions,orsyncope.Hehadanintermediateprobabilityofcor-onaryarterydisease,basedonhisglobalriskscore.Hismed-ical history was significant for myocarditis 20 years earlier.There was no history of coagulation or connective tissue dis-order. Resting electrocardiogram demonstrated first-degreeatrioventricular heart block but was otherwise unremark-able. Transthoracic echocardiography revealed a left ventric-ular (LV) ejection fraction of 50% and grade I diastolic dys-function with normal LV chamber size and wall motion.Stress myocardial perfusion imaging (MPI) with treadmilland adenosine challenge demonstrated normal right ventri-clephysiology;LVejectionfractionof62%;andamoderately-sized, mild inferoseptal and inferior, partially reversible per-fusion defect consistent with impaired flow reserve in themid-to-distal right coronary artery (RCA).Coronary computed tomography (CT) angiogram per-formedtoevaluatethecoronaryarteriesrevealedadistalRCAnoncalcified plaque causing less than 50% reduction in lu-mendiameter,andanill-defined3 4-cmfocalfillingdefectin the left ventricle near the apex. The filling defect had abroad surface of contact with the endocardium, was low inattenuationrelativetothemyocardium,persistedthroughoutthecardiaccycleoncineimages,andhadminimalmovementor morphologic change during the cardiac cycle. Poorly or-ganized thrombus was suspected (Fig. 1).Three weeks after the CT, transthoracic echocardiographyperformedusingahigh-frequencytransducertoevaluatetheLV apex in multiple apical planes demonstrated normal wallmotion and contractility and apical trabeculations andpseudochordae, which were presumed to correspond to theabnormality on CT (Fig. 2). Because of the conflicting find-ings, 3 weeks later, cardiac magnetic resonance imaging(MRI) was performed to evaluate the LV filling defect. MRIevaluation included black-blood imaging, balanced steady-state free precession cine sequences, and delayed enhance-ment sequences (Fig. 3). The black-blood images showedartifact related to slow flow in the LV apex, and the cinesequences demonstrated slow and turbulent flow at the LVapex; there was no filling defect on delayed enhancementimages to correspond to a LV thrombus. No anticoagulationtherapy was initiated in the interim between CT, echocardi-ography, and MRI.

Background— There are no randomized, controlled trial data to support the benefit of β-blockers in patients with asymptomatic left ventricular systolic dysfunction. We investigated whether β-blocker therapy ameliorates left ventricular remodeling in asymptomatic patients with left ventricular systolic dysfunction. Method and Results— Patients with left ventricular ejection fraction 2 ), and left ventricular ejection fraction (27%). At 12 months in the 200-mg group, there was a 14±3 mL/m 2 decrease (least square mean±SE) in end-systolic volume index and a 6±1% increase in left ventricular ejection fraction ( P P P Conclusion— β-Blocker therapy can ameliorate left ventricular remodeling in asymptomatic patients with left ventricular systolic dysfunction.

Idiopathic premature ventricular complexes (PVCs) usually are considered benign, even when frequent. However, case reports have demonstrated a possible link between frequent PVCs and left ventricular (LV) dysfunction. In addition, frequent PVCs recently were demonstrated to be associated with increased LV dimensions and cardiomyopathy.Among 60 consecutive patients with idiopathic, frequent PVCs (10/hour), a reduced LV ejection fraction (EF; mean 34% +/- 13%) was present in 22 (37%) patients. Patients with decreased LV function had a greater PVC burden on a 24-hour Holter monitor than patients with normal EF (37% +/- 13% vs. 11% +/- 10% of all QRS complexes; P.0001). There was a significant inverse correlation between the PVC burden and the EF before ablation (r = 0.73, P.0001).The PVCs originated in the right ventricular outflow tract in 31 (52%) of 60 patients, the LV outflow tract in 9 (15%) of 60 patients, and in other sites in 13 (22%) of 60 patients. The site of PVC origin could not be determined in seven patients. Ablation was completely successful in 48 (80%) patients. In patients with an abnormal EF before ablation, LV function normalized in 18 (82%) of 22 patients from a baseline of 34% to 59% +/- 7% (P.0001) within 6 months. In the four patients in whom ablation was ineffective, the EF further declined from 34% +/- 10% to 25% +/- 7% (P = .06) during follow-up. In a control group of 11 patients with a similar PVC burden (30% +/- 8%) and a reduced EF (28% +/- 13%) who did not undergo ablation, the EF remained unchanged in 10/11 patients over 19 +/- 17 months of follow-up and one patient underwent heart transplantation.LV dysfunction in the setting of frequent, idiopathic PVCs may represent a form of cardiomyopathy that can be reversed by catheter ablation of the PVCs.

Background Acute type A aortic dissection (AAD) remains a highly lethal entity for which emergent surgical correction is standard care. Prior studies have identified specific clinical findings as being predictive of outcome. The prognostic significance of specific findings on imaging studies is less well described. We sought to identify the prognostic value of transesophageal echocardiography (TEE) in medically and surgically treated patients with AAD. Methods We studied 522 AAD patients enrolled over 6 years in the International Registry of Acute Aortic Dissection who underwent TEE. Multivariate analysis identified independent associations of inhospital mortality, first using clinical variables (model 1), after which TEE data were added to build a final model (model 2). Results Inhospital mortality was 28.7%. Transesophageal echocardiographic evidences of pericardial effusion ( P = .04), tamponade ( P P = .02), and patent false lumen ( P = .08) were more frequent in nonsurvivors. Dilated ascending aorta ( P = .03), dissection localized to the ascending aorta ( P = .02), and thrombosed false lumen ( P = .08) were less common in nonsurvivors. Model 1 identified age ≥70 years, any pulse deficit, renal failure, and hypotension/shock as independent predictors of death. Model 2 identified dissection flap confined to ascending aorta (odds ratio 0.2, 95% CI 0.1-0.6) and complete thrombosis of false lumen (odds ratio 0.15, 95% CI 0.03-0.86) as protective. In the medically treated group, mortality was 31% for subjects with a partially or completely thrombosed false lumen versus 66% in the presence of a patent false lumen. Conclusions Transesophageal echocardiography provides prognostic information in AAD beyond that provided by clinical risk variables.

ObjectivesWe sought to evaluate the clinical characteristics, management, and outcomes of elderly patients with acute type A aortic dissection.BackgroundFew data exist on the clinical manifestations and outcomes of acute type A aortic dissection in an elderly patient cohort.MethodsWe categorized 550 patients with type A aortic dissection enrolled in the International Registry of Acute Aortic Dissection into two age strata (

Background — Given the high mortality rates in patients with type A aortic dissection, predictive tools to identify patients at increased risk of death are needed to assist clinicians for optimal treatment. Methods and Results — Accordingly, we evaluated 547 patients with this diagnosis enrolled in the International Registry of Acute Aortic Dissection (IRAD) between January 1996 and December 1999. Univariate testing followed by multivariate logistic regression analysis was performed to identify independent predictors of death. In-hospital mortality rate was 32.5% in type A dissection patients. In-hospital complications (neurological deficits, altered mental status, myocardial or mesenteric ischemia, kidney failure, hypotension, cardiac tamponade, and limb ischemia) were increased in patients who died compared with survivors ( P P =0.03), abrupt onset of chest pain (OR 2.60; 95% CI, 1.22 to 5.54; P =0.01), hypotension/shock/tamponade (OR, 2.97; 95% CI, 1.83 to 4.81; P P =0.002), pulse deficit (OR, 2.03; 95% CI, 1.25 to 3.29, P =0.004), and abnormal ECG (OR, 1.77; 95% CI, 1.06 to 2.95; P =0.03) (area under receiver operating curve, 0.74; Hosmer-Lemeshow statistic, P =0.75). Conclusions — The in-hospital mortality rate in acute type A aortic dissection is high and can be predicted with the use of a clinical model incorporated in a simple risk prediction tool. This tool can be used to educate patients with dissection about their predicted risk and in clinical research for risk adjustment while comparing outcomes of different therapies.

The purpose of this study was to evaluate the ability of novel Doppler indices of left ventricular (LV) systolic and diastolic function to predict survival in patients with congestive heart failure (CHF).Congestive heart failure is associated with an increased risk of death or cardiac transplantation, yet techniques to predict survival are limited.Doppler-derived dP/dt and - dP/dt were determined prospectively from the continuous-wave Doppler spectrum of the mitral regurgitation jet (dP/dt = 32/time between 1 and 3 m/s; -dP/dt = 32/time between 3 and 1 m/s) in 56 patients with chronic CHF (age, 60 +/- 15 years; LV ejection fraction, 23 +/- 9%). Baseline clinical and echocardiographic variables were also obtained, and clinical follow-up was performed in all patients.Twenty-four patients experienced a primary event of cardiac death (n = 15), United Network for Organ Sharing status I (inotrope-dependent) heart transplant (n = 3) or urgent implantation of a LV assist device (n = 6). Doppler-derived dP/dt (dichotomized toor = or600 mm Hg/s; p = 0.0002) and -dP/dt (trichotomized to450, 450 to 550 and550 mm Hg/s; p = 0.0001) predicted event-free survival, as did Doppler-derived risk groups determined by the combination of the two (low risk, dP/dtor = 600; intermediate risk, dP/dt600 and -dP/dtor = 450; high risk, dP/dt600 and -dP/dt450; p = 0.0001). Multivariable analysis revealed Doppler-derived risk groups, intravenous inotrope requirement and blood urea nitrogen as significant independent predictors of outcome.New Doppler indices of dP/dt, - dP/dt and risk groups defined by the combination of dP/dt and -dP/dt predict event-free survival in patients with CHF.

Aggressive management to reduce pulmonary artery systolic pressure (PASP) and pulmonary capillary wedge pressure (PCWP) reduces hospitalization rates and is crucial for patients awaiting transplantation but may require periodic invasive monitoring with right heart catheterization.The purpose of this study was to define the relation of transpulmonary passage of Albunex (Mallinckrodt Medical, St Louis, Mo) to intracardiac hemodynamics and clinical outcome in patients with chronic congestive heart failure (CHF). Patients (n = 38) with chronic CHF underwent graded dobutamine infusion (baseline, 5, 10, 20 microg/kg per minute; 5-minute stages) with 5.0 mL Albunex injected intravenously at each stage. The dobutamine dose at which Albunex appeared in the left ventricle was determined. All patients had right heart catheterization to determine PASP and PCWP.Transpulmonary passage of Albunex at baseline or at 5 microg/kg per minute dobutamine infusion predicted PCWP20 mm Hg with a positive predictive value of 100% and a negative predictive value of 79%. Initial appearance of Albunex in the left ventricle at a dobutamine dose of 20 microg/kg per minute or failure to appear at any dose predicted a PCWP20 mm Hg with a positive predictive value of 100% and a negative predictive value of 94%. No patient with Albunex passage at baseline sustained a major adverse event. Major adverse events occurred in 11 of 21 patients in whom Albunex either failed to cross or crossed the pulmonary bed at a dose of 20 microg/kg per minute of dobutamine.In patients with chronic CHF, transpulmonary passage of Albunex during dobutamine infusion can be used to predict both elevated and normal intracardiac pressures and to identify a subset of patients at high risk for an adverse outcome.

This study was undertaken to determine the prognostic significance of hypotension induced during preoperative dobutamine stress echocardiography (DSE) before vascular and noncardiac thoracic surgery. Wall motion abnormality during DSE predicts perioperative risk. Although hypotension during DSE has not been shown to correlate with the presence or severity of coronary artery disease, its significance in perioperative risk assessment is unknown. We retrospectively studied 300 patients who had DSE within 6 months of noncardiac surgery. Perioperative events including death, myocardial infarction, ischemia, and arrhythmias were recorded. Odds ratios with 95% confidence intervals were used to examine the association between clinical and echocardiographic variables and perioperative events. A hypotensive response during DSE was seen in 85 patients (28%). Forty-eight patients (16%) had 54 perioperative complications including 4 cardiac-related deaths, 10 myocardial infarctions, 12 myocardial ischemic events, and 28 arrhythmias. Hypotension during DSE was predictive of the combined end point of perioperative cardiac mortality, myocardial infarction, and ischemia (odds ratio 4.04, 95% confidence interval 1.72 to 9.51). In a multivariate logistic regression model, hypotension during DSE remained a significant predictor (odds ratio 4.10, p

Background: Lung volume reduction surgery has been proposed as a bridge to lung transplantation and as definitive therapy for advanced chronic obstructive lung disease. However, patient selection criteria and optimal preoperative assessment have not been clearly defined. Objective: We investigated the feasibility, safety, and value of dobutamine stress echocardiography as a predictor of major early cardiac events in patients who underwent lung volume reduction surgery. Methods: The study population consisted of 46 patients (21 men and 25 women, mean age 59 ± 9 years) who underwent dobutamine stress echocardiography (maximum dose 40 μg · kg –1 · min –1 plus atropine if needed) 180 days or less before lung volume reduction surgery. Adverse cardiac events were prospectively defined and tabulated during hospitalization after the operation and at subsequent outpatient visits. Results: Dobutamine stress echocardiography was interpretable in 45 of 46 (98%) patients. There were no adverse events during testing. The studies revealed normal left ventricular systolic function at rest in all patients and normal right ventricular function in all patients but one. Thirteen patients had right ventricular enlargement. Estimated right ventricular systolic pressure was mildly elevated (>40 mm Hg) in 5 patients. Four patients (9%) had stress tests positive for ischemia. There were no perioperative deaths. Follow-up was available for 44 of 45 patients at a duration of 20.0 ± 7.0 months. Two major adverse cardiac events occurred in the same patient in whom the results of dobutamine stress echocardiography were positive for ischemia (positive predictive value 25%, 95% confidence interval 0% to 83%; negative predictive value 100%, 95% confidence interval 90 to 100%). Conclusion: Despite end-stage chronic obstructive lung disease and poor ultrasound windows, dobutamine stress echocardiography is feasible and safe in patients undergoing evaluation for lung volume reduction surgery. It yields important information on right and left ventricular function and has an excellent negative predictive value for early and late adverse cardiac events. (J Thorac Cardiovasc Surg 1999;118:542-6)

Primary pulmonary hypertension (PPH) is essentially a diagnosis of exclusion and usually is made late because of the nonspecific nature of the early signs and symptoms. Echocardiography is a key screening test in the diagnostic algorithm of patients with suspected PPH. The purpose of this study was to define the echocardiographic Doppler features in patients with PPH at the time of diagnosis. From 1992 to 1997, 51 patients were diagnosed with PPH at our institution. All underwent a standardized transthoracic echocardiographic examination, including a contrast study and transthoracic echocardiographic examination if indicated. Pulmonary artery systolic pressure was calculated from the tricuspid regurgitation jet. The majority of patients had pulmonary artery systolic pressure greater than 60 mm Hg (96%) associated with systolic flattening of the interventricular septum (90%), enlarged right atrium (92%) and ventricle (98%), and reduced right ventricular systolic function (76%). There was an increase in the interventricular septal thickness (>1.2 cm) in 21 (43%) of 49 patients, accompanied by a septal/posterior wall ratio greater than 1.3 in 11 (22%) of 49. Although a reduction in both left ventricular systolic and diastolic volumes was noted, global left ventricular systolic function was preserved in all patients. Mitral E/A ratio was less than 0.7 in 7 (22%) patients studied. Color Doppler revealed moderate to severe tricuspid regurgitation and pulmonic insufficiency in 41 (80%) of 51 and 16 (31%) of 51 of cases, respectively. Pericardial effusion (7 small and 1 moderate) and patent foramen ovale (n = 12) were also frequently detected. At the time of initial diagnosis, PPH is associated with secondary cardiac abnormalities in the majority of patients. (J Am Soc Echocardiogr 1999;12:655-62.)

Background The mechanism by which dobutamine induces ischemia is thought to depend on both increased chronotropy and inotropy. No data have been reported on the diagnostic power of dobutamine stress echocardiography (DSE) among patients with fixed-rate pacemakers and absolute chronotropic incompetence. The purpose of this study was to determine the diagnostic and prognostic utility of DSE in patients with fixed-rate, demand ventricular pacing who had no heart rate (HR) increase during DSE. Methods From 1990 to 1997, 22 patients remained pacemaker dependent with a fixed HR (69.7 ± 5.7 beats/min) throughout DSE. Myocardial perfusion single-photon emission computed tomography and coronary angiographic studies were reviewed when available. Clinical follow-up was determined for all patients at 15.4 ± 7.7 months. Results In spite of absolute chronotropic incompetence during DSE, 11 (50%) of 22 patients had test results consistent with inducible ischemia. Coronary artery disease was confirmed in 6 (75%) of 8 who had coronary angiograms. Three of 11 patients with negative DSE underwent coronary angiography that confirmed the absence of significant coronary artery disease. DSE had a sensitivity of 100% and specificity of 60% in pacemaker-dependent patients with absolute chronotropic incompetence. At the time of clinical follow-up, none of the patients with no inducible ischemia on DSE had an adverse ischemic cardiac event. Conclusions This study suggests that DSE has preserved diagnostic and prognostic utility in pacemaker-dependent patients with absolute chronotropic incompetence. (Am Heart J 1999;138:364-8.)

BACH, DAVID S., AILA M. RISSANEN, CARL M. MENDEL, GILLIAN SHEPHERD, STEVEN R. WEINSTEIN, FINIAN KELLY, TIMOTHY B. SEATON, BABABHAI PATEL, TUULA A. PEKKARINEN, AND WILLIAM F. ARMSTRONG. Absence of cardiac valve dysfunction in obese patients treated with sibutramine. Obes Res. Objective: Serotonin-releasing agents prescribed as weight-loss medications have been implicated as a cause of acquired aortic and mitral valve abnormalities. Sibutramine hydrochloride (MERIDIA®) is a serotonin and norepi-nephrine reuptake inhibitor with proven efficacy of weight reduction. The purpose of this study was to determine the incidence of cardiac valve disease in sibutramine-treated patients. Research Methods and Procedures: Obese patients with type 2 diabetes mellitus enrolled in an ongoing double-blind, placebo-controlled, parallel-arm, 12-month study of sibutramine (followed by a 12-month open label extension) underwent transthoracic echocardiographic imaging and color Doppler interrogation for assessment of cardiac valve anatomy and function. Results: A total of 210 patients were evaluated. Of these, 133 were receiving sibutramine (72 in the double-blind period), and 77 were receiving placebo. The mean ± Standard Deviation age was 54±9 years, and the mean duration of treatment was 229±117 days (approximately 7. 6 months). The prevalence of left-sided cardiac valve dysfunction was low and similar for the two treatment groups (sibutramine 31133, or 2. 3%; placebo 2/77, or 2. 6%). All five cases were cases of aortic insufficiency; four were mild, one was severe (in a placebo patient). All three sibutramine cases were patients over age 50; two had a history of systemic hypertension. Conclusion: The prevalence of left-sided cardiac valve dysfunction was not higher than background in obese patients treated with sibutramine for an average of 7. 6 months.

Background —Conversion of chronic atrial fibrillation (AF) is associated with atrial stunning, but the short-term effect of a brief episode of AF on left atrial appendage (LAA) emptying velocity is unknown. The purpose of this study was to determine whether a short episode of AF affects left atrial function and whether verapamil modifies this effect. Methods and Results —The subjects of this study were 19 patients without structural heart disease undergoing an electrophysiology procedure. In 13 patients, LAA emptying velocity was measured by transesophageal echocardiography in the setting of pharmacological autonomic blockade before, during, and after a short episode of AF. During sinus rhythm, the baseline LAA emptying velocity was measured 5 times and averaged. AF was then induced by rapid right atrial pacing. After either spontaneous or electrical conversion, LAA emptying velocity was measured immediately on resumption of sinus rhythm and every minute thereafter. The mean duration of AF was 15.3±3.8 minutes. The mean baseline emptying velocity was 70±20 cm/s. The first post-AF emptying velocity was 63±20 cm/s ( P =0.02 versus baseline emptying velocity). The post-AF emptying velocity returned to the baseline emptying velocity value after 3.0 minutes. The mean percent reduction in post-AF emptying velocity was 9.7±21% (range, 15% increase to 56% decrease). A second group of 6 patients were pretreated with verapamil (0.1-mg/kg IV bolus followed by an infusion of 0.005 mg · kg −1 · min −1 ). In these patients, the first post-AF emptying velocity, 58±14 cm/s, was not significantly different from the pre-AF emptying velocity, 60±13 cm/s ( P =0.08). Conclusions —In humans, several minutes of AF may be sufficient to induce atrial contractile dysfunction after cardioversion. When atrial contractile dysfunction occurs, there is recovery of AF within several minutes. AF-induced contractile dysfunction is attenuated by verapamil and may be at least partially mediated by cellular calcium overload.

OBJECTIVES The aim of this study was to explore the full range of tricuspid valve regurgitation velocity (TRV) at rest and with exercise in disease free individuals. Additionally we examined the relationship of stroke volume (SV), cardiac output (CO) and TRV to exercise capacity. BACKGROUND Doppler evaluation of TRV can be used to estimate pulmonary artery systolic pressure (PASP). Most studies have assumed TRV ≤2.5 m/s as the upper limits of normal. The full range of TRV with exercise has been incompletely defined. METHODS Highly conditioned athletes (n = 26) and healthy, active, young male volunteers (n = 14) underwent standardized recumbent bicycle exercise. Exercise parameters included: TRV, SV, CO, systolic (SBP) and diastolic (DBP) systemic blood pressure. RESULTS Tricuspid valve regurgitation, SV, HR and CO were significantly higher in athletes than in nonathletes over all workloads, including rest. Systolic blood pressure and DBP did not show significant differences between the two groups. CONCLUSIONS This study defines the upper physiologic limits of TRV at rest and during exercise in normals and provides a noninvasive standard for the diagnosis of pulmonary hypertension.

Objectives The objective of this study was to define the range of clinical presentations, echocardiographic findings, and underlying final diagnoses in patients with clinically suspected acute aortic dissection. Methods and Results This study was designed as a retrospective review of clinical and echocardiographic data in consecutive patients evaluated for clinically suspected acute aortic dissection. The study population consisted of 75 studies in 74 consecutive patients referred for urgent or emergency evaluation because of signs and symptoms suggesting acute aortic dissection. A history and physical examination designed to elicit the cause of chest pain, evidence of congestive heart failure, and other cardiovascular abnormalities was performed in each patient. All patients underwent transesophageal echocardiography by experienced operators. Routine 12-lead electrocardiograms and chest radiographs were available for review in the majority of patients. Magnetic resonance imaging or computed tomography was performed in only 5 (6%) and 34 (44%) patients, respectively. Contrast aortography was performed in 21 (27%) patients. For the entire patient cohort, the most prevalent symptom was chest pain alone ( n = 31; 41%) or chest pain in conjunction with back pain ( n = 23; 31%). Classic "tearing" pain was an infrequent symptom. Syncope or other neurologic findings were present in 15 (20%) patients. Acute aortic dissection was responsible for 34 (45%) of the 75 presentations, with 31 (41% of total evaluations, 92% of dissections) involving the ascending aorta (Stanford type A, DeBakey type 1 or 2). Alternate major cardiovascular diagnoses, including acute myocardial infarction, primary valvular disease, or pericardial disease, were established in 12 (16%) cases. Aortic pathology, other than dissection, was found in 15 (20%) cases. Transesophageal echocardiography established the diagnosis responsible for the symptoms in 61 (81%) cases. Conclusions Symptoms in patients with acute aortic dissection are more variable than commonly recognized. Transesophageal echocardiography is an accurate primary diagnostic tool in patients with clinically suspected acute aortic dissection. It allows rapid diagnosis of dissection and can identify alternate cardiovascular pathology responsible for the symptoms in a significant number of patients without acute dissection. (Am Heart J 1998;136:1051-60.)

With use of transesophageal echocardiography, the short-term effects of transthoracic electrical cardioversion of atrial flutter (AFI) on atrial mechanical function and spontaneous echo contrast were determined. Thirty patients who had AFI for a mean of 6.4 +/- 12.2 months underwent transthoracic cardioversion. A transesophageal echocardiogram was recorded immediately before cardioversion, and left atrial appendage emptying velocity and spontaneous contrast were assessed serially at 1, 3, and 5 minutes after cardioversion in 28 patients, and also at 8, 10, and 15 minutes after cardioversion in a subgroup of 13 patients. Cardioversion was deferred in 2 patients (7%) because a thrombus was found in the left atrial appendage. Before cardioversion, spontaneous contrast was present in the left atrium in 7 of 28 patients (25%) who underwent cardioversion. The mean left atrial appendage emptying velocity of 54 +/- 22 cm/s before cardioversion fell by 26% to 40 +/- 25 cm/s at 1 minute after restoration of sinus rhythm (p

Doppler tissue imaging (DTI) is a new noninvasive imaging modality that directly interrogates myocardial velocity with high temporal and spatial resolution. This study was designed to test the hypothesis that quantitative DTI provides unique information regarding regional myocardial systolic and diastolic function during acute ischemic events. Myocardial velocities were quantified during the acute ischemic and reperfusion phases of 13 elective percutaneous coronary angioplasty procedures in 12 patients. In myocardium subtended by angioplasty vessels, peak velocities decreased during occlusive balloon inflation (from 21.2 +/- 9.8 to -0.6 +/- 4.0 mm/sec in systole [p < 0.001] and from 21.7 +/- 9.2 to -0.6 +/- 3.9 mm/sec in diastole [p < 0.001]). During early reperfusion, velocities exceeded those observed at baseline (p = 0.003). In regions remote from the treated artery, peak myocardial velocities increased in the absence of significant stenosis but remained unchanged or decreased in the presence of significant stenosis of the associated vessel. We conclude that (1) myocardial velocities rapidly decrease during acute ischemia and show a rebound increase after reperfusion, and (2) in regions remote from ischemia, velocities display distinct patterns on the basis of the presence or absence of obstructive coronary disease in the associated vessel. Quantitative DTI is a useful tool for the assessment of myocardial velocity and may provide new insights into myocardial systolic and diastolic function.

Although the accuracy of dobutamine stress echo (DSE) for detecting coronary artery disease (CAD) has been established, its role in determining prognosis is less well defined. The purpose of this study was to evaluate the prognostic significance of DSE in patients with known or suspected CAD. Follow-up was obtained on 291 patients an average of 15 months after clinically indicated DSF. Studies were stratified with respect to resting and inducible wall motion abnormalities into 1 of 4 responses: normal, ischemic, fixed, and mixed. Hard end points of nonfatal myocardial infarction and cardiac death were tabulated for outcome. Statistically significant differences in the incidence of hard cardiac end points were noted for 2 of 4 DSE responses. A normal DSE was associated with a statistically lower likelihood of a hard cardiac event than was a DSE demonstrating resting or inducible abnormalities (p = 0.001). DSE with a mixed response (resting abnormality with additional inducible ischemia) was associated with a higher likelihood of cardiac events by multivariate analysis (p = 0.003). By multiple logistic regression analysis of dobutamine response, age, and cardiac risk factors, only a mixed response on DSE was independently associated with the occurrence of a hard cardiac event in the follow-up period. In addition, left ventricular dysfunction on the resting echocardiogram was associated with a worse prognosis in patients with major noncardiac disease. We conclude that dobutamine response is an independent predictor of cardiac events compared with traditional risk factor analysis and that DSE can identify high- and low-risk subsets of patients with known or suspected CAD. (Am J Cardiol 1996;78:404–408)

Doppler tissue imaging (DTI) is a new echocardiographic imaging technique from which quantitative data regarding myocardial velocity can be extracted. The purpose of this study was to compare endocardial velocities determined from DTI with those determined from M-mode echocardiography and to assess the range of myocardial velocities in normal subjects. Nineteen subjects were evaluated by M-mode echocardiography and quantitative DTI for maximal systolic velocities of the anteroseptal and inferoposterior walls. Mid-myocardial and epicardial velocities were also measured by DTI for each wall. Maximal systolic velocities of the anteroseptal and inferoposterior endocardium determined by DTI correlated significantly with those derived from M-mode echocardiography (r = 0.87). The velocity of the inferoposterior wall by DTI (27.3 +/- 4.8 mm/sec) was greater than that of the anteroseptum (20.8 +/- 4.1 mm/sec) by a mean difference of 7.0 +/- 5.7 mm/sec (p0.001). A peak velocity gradient of 5.9 +/- 3.5 mm/sec (p0.001) between the epicardium to endocardium was detected. These data confirm that (1) regional myocardial velocities may be quantified with DTI in human beings; (2) the high resolution of DTI allows velocities to be determined at different levels within the myocardium; and (3) heterogeneity of myocardial velocities may be demonstrated in normal subjects.

Objectives. This study was designed to characterize the clinical, echocardiographic and angiographic findings in patients who have regional wall motion abnormalities predictive of coronary artery disease on dobutamine stress echocardiograms, although coronary angiography reveals no critical stenoses. Background. The specificity of dobutamine stress echocardiography has been reported to be lower than its sensitivity; the sources of false positive findings on dobutamine stress echocardiograms have not been previously defined. Methods. Clinical and echocardiographic characteristics were retrospectively reviewed for patients who had both a dobutamine stress echocardiogram indicate of coronary artery disease on the basis of wall motion abnormalities and

We describe the clinical and echocardiographic findings in eight patients with right atrial spontaneous echo contrast who were identified from 648 consecutive patients undergoing transesophageal echocardiography. Common findings in these patients were right atrial enlargement (8 patients), tricuspid regurgitation (7 patients), atrial fibrillation or flutter (6 patients), elevated right ventricular pressure (5 patients), moderate or severe mitral valve disease (5 patients), and right to left interatrial shunts (3 patients). Right heart catheterization in three patients showed markedly elevated right atrial, right ventricular, and pulmonary artery pressures. Two patients had thromboembolic events-one patient had recurrent pulmonary emboli, and another patient with an atrial septal aneurysm had recurrent transient ischemic attacks. Right atrial echo contrast is an uncommon finding at echocardiography that is associated with severe right heart dysfunction. It may also be associated with paradoxical or pulmonary embolism.

Frequent idiopathic premature ventricular complexes (PVCs) can result in a reversible form of cardiomyopathy. In this study, the determinants of PVC-induced left ventricular (LV) dysfunction were assessed.The subjects of this study were 241 consecutive patients (115 men [48%], mean age 48 ± 14 years) referred for ablation of frequent PVCs. One hundred eighty patients (75%) experienced palpitations and 61 (25%) did not. The PVC burden was determined by 24-hour Holter monitoring, and echocardiograms were performed to assess LV function. An LV ejection fraction of50% was considered abnormal.LV ejection fraction (mean 0.36 ± 0.09) was present in 76 of 241 patients (32%). There was a higher prevalence of males among the patients with PVC cardiomyopathy compared to patients with normal LV function (51/76 [67%] vs 64/165 [39%]; P.0001). The mean PVC burden was significantly higher in patients with PVC cardiomyopathy than in patients with normal LV function (28% ± 12% vs 15% ± 13%; P.0001). Among symptomatic patients, those with cardiomyopathy had a significantly longer duration of palpitations (135 ± 118 months) compared with patients with normal LV function (35 ± 52 months; P.0001). The proportion of asymptomatic patients was significantly higher in the presence of cardiomyopathy (36/76, 47%) than in normal LV function (25/165, 15%; P.0001). Symptom duration of 30 to 60 months, symptom duration60 months, the absence of symptoms, and the PVC burden in asymptomatic patients were independent predictors of impaired LV function (adjusted odds ratio [95% confidence interval]: 4.0 [1.1-14.4], 20.1 [6.3-64.1], 13.1 [4.1-37.8], and 2.1 [1.2-3.6], respectively).The duration of palpitations and the absence of symptoms are independently associated with PVC-induced cardiomyopathy.

Objectives. The aim of this study was to use positron emission tomography (PET)-derived carbon (C)-11 acetate kinetics to determine the effects of dobutamine on oxidative metabolism and its effects on myocardial efficiency in a group of patients with dilated cardiomyopathy. Background. Dobutamine is known to improve myocardial function but may do so at the expense of myocardial oxygen consumption, which could be a potential deleterious effect. Carbon-11 aceate kinetics correlate with myocardial oxygen consumption as shown in animal models. Combining these scintigraphic measurements of oxygen consumption with estimates of cardiac work results in a work-metabolic index, which reflects cardiac efficiency. Methods. Eight patients with nonischemic dilated cardiomyopathy underwent dynamic PET imaging, echocardiography and hemodynamic measurements. Seven of these patients were also studied while receiving dobutamine. Direct measurements of myocardial oxygen consumption using coronary sinus catheterization were obtained with eight of the PET studies to validate C-11 acetate in patients with cardiomyopathy. Results. The mean (± SD) C-11 clearance rate significantly increased with dobutamine from 0.105 ± 0.027 to 0.155 ±0.023 min−1(p = 0.001). Directly measured myocardial oxygen consumption had a linear relation to the mean C-11 clearance rate (r = 0.8, p = 0.018). Dobutamine was noted to significantly reduce systemic vascular resistance as well as the severity of mitral regurgitation. The work-metabolic index determined using hemodynamic variables and PET data increased from 2 ± 0.7 × 104to 2.6 ± 0.6 × 104(p = 0.04). Efficiency, estimated by employing the oxygen consumption to k2relation, also increased from 13 ± 4.5% to 16.9 ± 6.4% (p = 0.04). Conclusions. Despite an increase in myocardial oxygen consumption, dobutamine led to an increase in work-metabolic index in patients with dilated nonischemic cardiomyopathy. Dobutamine reduced systemic vascular resistance and mitral regurgitation, suggesting that in this group of patients, it had important vasodilatory action in addition to its inotropic effects. The use of the C-11 acetate PET for determining myocardial oxygen consumption and estimating efficiency could potentially complement existing clinical measures of ventricular performance and may allow improved and objective evaluation of therapy in patients with heart failure.

The problems of population referral bias in the calculation of specificity in diagnostic testing for coronary artery disease have been previously described. Previous studies investigating the sensitivity and specificity of dobutamine stress echocardiography (DSE) have been subject to pretest and posttest referral biases, largely as a result of the requirement for coronary arteriography. This study determines the normalcy rate for DSE by examining a population at statistically low risk for coronary artery disease. The probability of significant coronary artery disease was determined for 828 consecutive patients referred for DSE at the University of Michigan, and groups were identified with10% and5% probability of disease. Four of 72 patients (5.6%) with a normal baseline echocardiogram and a probability of coronary artery disease of10%, and three of 38 (7.9%) with a probability of5% were found to have an abnormal DSE, yielding normalcy rates of 94.4% and 92.1%, respectively. The area of abnormality involved the posterior circulation in three of four patients (75%). This study demonstrates that DSE has a normalcy rate of 92% to 94% and is an accurate test for excluding the presence of significant coronary artery disease.

investigated formally, we are unaware of any specific predisposing factors for the development of SANRT in these patients. All 5 patients had placement of atrial cannulas in standard fashion in the right atrial appendage, whereas the 4 patients undergoing Norwood I had concomitant standard atrial septectomy. However, given the association with hypoplastic left heart syndrome, one must wonder if there is an inherent abnormality of the sinus node that predisposes these patients to SANRT.

Myocardial contrast echocardiography has been found to be a safe and useful technique for evaluating relative changes in myocardial perfusion and delineating areas at risk. Although earlier contrast agents required direct delivery into the coronary arteries or aortic root, a new echocardiographic contrast agent, sonicated albumin microspheres (Albunex), has been found to cross the pulmonary circulation in experimental models.To determine the safety and preliminary efficacy of intravenous injections of Albunex in humans, 71 patients at three independent medical institutions underwent two-dimensional echocardiographic examination before, during and after the administration of three intravenous doses of Albunex, ranging from 0.01 to 0.12 ml/kg body weight. All patients provided a complete history and underwent physical and neurologic examination and laboratory and electrocardiographic evaluation before the injections; all evaluations (except for the history) were repeated at 2 h and 3 days after the injections of Albunex. The efficacy of the injections was qualitatively assessed by two independent blinded observers using a grading system of 0 to + 3, with 0 indicating an absence of contrast effect and + 3 indicating full opacification of the cavities examined.All injections were well tolerated and no serious side effects were noted in any of the patients. Irrespective of dose group, a cavity opadfication ≥ + 2 was seen in the right ventricle in 212 (88%) of 240 injections and in the left ventricle in 151 (63%) of 240 injections as judged by the independent observers. The degree of ventricular cavity opacification appeared to be dose and concentration related. In conclusion, this first multicenter clinical study of Albunex demonstrates that the contrast agent is safe when administered Intravenously and achieves significant transpulmonary passage in a majority of patients.

Background: During cardiac resynchronization therapy (CRT), cardiac performance is dependent on an optimized atrioventricular delay (AVD). However, the optimal AVD at different heart rates has not been defined yet during CRT. Method: The effects of an increase in heart rate by pacing or physical exercise on optimal AVD were studied in 36 patients with biventricular pacemakers/defibrillators. The velocity time integral (VTI) in the left ventricular outflow tract (LVOT) was measured with pulsed Doppler either at three different paced heart rates in the supine position or in seated position before and after physical exercise. Results: The baseline AVD was optimized to 99 ± 19 ms in the supine and 84 ± 22 ms in the seated position. When the heart rate was increased by DDD pacing, there was a positive linear relationship between an increase in heart rate, in AVD and in VTI (LVOT-VTI + 0.047 cm/s per 10 beats per minute (bpm) heart rate increase per 20 ms increase in AVD, P = 0.007). A similar but more pronounced relationship was found after physical exercise in the seated position (LVOT-VTI + 0.146 cm/s per 10 bpm heart rate increase per 20 ms increase of AVD, P = 0.013). This effect was observed in patients with and without AV block and mitral regurgitation. Conclusions: In conclusion, the systolic performance of the dilated ventricle, which depends on an elevated preload, is critically affected by the appropriate timing of the AVD during exercise. In contrast to normal pacemaker patients, in CRT the relatively short baseline AVD should be prolonged at increased heart rates. Further studies with other means of measuring exercise cardiac performance are needed to confirm these unexpected findings.

Background: Patients hospitalized in medical ICUs (MICUs) with acute noncardiac illnesses have an undefined prevalence of underlying cardiovascular abnormalities. Because of the acuteness of illness, the need for frequent concurrent mechanical ventilation, and the nature of the underlying diseases, routine cardiac examination may be suboptimal for identifying concurrent cardiac abnormalities. Purpose: The purpose of this study was to utilize transthoracic echocardiography and Doppler echocardiography interrogation to identify the range and prevalence of occult cardiac abnormalities that may be present in patients admitted to an MICU. Methods: Over a 12-month period, 500 consecutive patients who had been admitted to the MICU of a large university tertiary care center underwent complete two-dimensional echocardiography and Doppler scanning within 18 h of admission. The final study population comprised 467 patients. No study subject had been admitted to the MICU for a primary cardiac diagnosis. Cardiovascular abnormalities were prospectively defined, and all echocardiograms were interpreted independently by blinded observers. Both MICU and overall mortality rates as well as length of stay were compared to the presence or absence of cardiac abnormalities. Results: One or more cardiac abnormalities was noted in 169 patients (36%). The average (SD) age of patients in the study was 52 17 years (age range, 17 to 100 years), and the average age was 57 18 years (age range, 18 to 93 years) in patients with underlying cardiac abnormalities. A single cardiac abnormality was noted in 103 patients (22%), two cardiac abnormalities were noted in 34 patients (7.2%), and three or more cardiac abnormalities were noted in 32 patients (6.8%). Based on subsequent requests for cardiac diagnostic studies, 67 patients (14.3%) were clinically suspected of having significant cardiovascular abnormalities, 39 of whom (58%) had one or more cardiac abnormalities on seen on echocardiography. Cardiac abnormalities were unsuspected in 130 of 169 patients (77%) and were only noted at the time they underwent surveillance echocardiography. Although there was no correlation between the presence of cardiac abnormalities and mortality, both MICU and hospital length of stay were increased in patients with cardiac abnormalities. Conclusion: A significant proportion of patients admitted to an MICU with noncardiac illness have underlying cardiac abnormalities, which can be detected with surveillance echocardiography at the time of admission. Cardiac abnormalities were associated with an increased length of stay but not with increased mortality. (CHEST 2002; 122:1370 –1376)

Mitral regurgitation (MR) and tricuspid regurgitation (TR) frequently develop in patients with left ventricular systolic dysfunction (LVSD). Ventricular volume overload that occurs in patients with MR and TR may lead to progression of myocardial dysfunction. We hypothesized that MR and TR would provide markers of risk in patients with LVSD.We reviewed clinical, electrocardiographic, and echocardiographic data on 1421 consecutive patients with LVSD (left ventricular ejection fractionor =35%). Predictors of survival (freedom from death or United Network for Organ Sharing [UNOS]-1 transplantation) were identified in a multivariable analysis with a Cox proportional hazards analysis. The impact of MR and TR (none to mild, moderate, or severe) then was assessed separately with Kaplan-Meier survival analysis.During the follow-up period (mean +/- SD, 365 +/-364 days), death occurred in 435 study subjects (31%) and UNOS-1 transplantation in 28 subjects (2%). Multivariable predictors of poor outcome included increasing MR and TR grade, cancer, coronary artery disease, and absence of an implantable cardiac defibrillator. Relative risk was 1.84 (95% CI 1.43-2.38) for severe MR and 1.55 (95% CI 1.14-2.11) for severe TR. Survival with Kaplan-Meier analysis related inversely to MR grade (none to mild 1004 +/-31 days, moderate 795 +/-34 days, severe 628 +/-47 days, P.0001) and TR grade (none to mild 977 +/-28 days, moderate 737 +/-40 days, severe 658 +/-55 days, P =.0001).Patients with severe MR or TR represent high-risk subsets of patients with LVSD. Future study is warranted to determine whether pharmaceutical or surgical strategies to relieve MR and TR have a favorable impact on survival.

Study objective: We assess an alternative accelerated clinical pathway approach to the management of patients with newly diagnosed or new-onset atrial fibrillation (AF). Methods: A prospective, randomized pilot study of 2 AF disease-management strategies was conducted at a single university hospital. A traditional approach of hospital admission versus an accelerated emergency department–based strategy with low-molecular-weight heparin and early cardioversion to sinus rhythm was assessed in a cohort of patients with uncomplicated AF. The primary end points were length of stay and total actual direct costs. Results: Eighteen patients were randomized over a 15-month period. The accelerated treatment strategy in the ED resulted in a substantial decrease in length of stay (2.1±2.3 versus P =.15). The clinical outcomes (rate of sinus rhythm at discharge and follow-up and complications caused by AF) related to AF were similar in the 2 groups. Conclusion: A disease-management strategy for new, uncomplicated AF that uses an ED-outpatient treatment pathway results in a shorter length of stay at potentially lower cost. The results of this pilot study warrant further investigation. [Kim MH, Morady F, Conlon B, Kronick S, Lowell M, Bruckman D, Armstrong WF, Eagle KA. A prospective, randomized, controlled trial of an emergency department–based atrial fibrillation treatment strategy with low-molecular-weight heparin. Ann Emerg Med. August 2002;40:187-192.]

Given the difference in risk factors, clinical presentation, and outcomes, clinicians should be vigilant for the presence of iatrogenic AD, particularly in those patients with unexplained hemodynamic instability or myocardial ischemia following invasive vascular procedures or CABG.

Triggered myocardial contrast echocardiography (MCE) has been used successfully to quantify myocardial blood flow and assess coronary stenosis in animal models, but practical considerations have limited its broad clinical use. Real-time MCE may have practical advantages to assess perfusion and real time myocardial blood flow in human beings. We compared real-time MCE with triggered imaging in 23 normal human volunteers by using an investigational ultrasound contrast agent (DMP-115) and a commercially available ultrasound platform (Acuson Sequoia). Peak myocardial opacification (reflecting myocardial blood volume) after contrast infusion was quantified digitally in gray scale units (GU). In 13 subjects, myocardial blood flow reserve was assessed during dipyridamole infusion with the use of intermittent destruction-replenishment techniques. Real-time MCE resulted in a 30- to 45-GU increase from baseline compared with a 20- to 70-GU increase with triggered imaging. Real-time MCE showed no statistical difference in opacification (P = .131 by analysis of variance) among any of the myocardial regions of interest. Triggered imaging resulted in heterogeneous opacification among the regions of interest (P.05 by analysis of variance). Dipyridamole did not significantly change peak myocardial opacification (myocardial blood volume) for either technique. Quantification of flow reserve revealed that myocardial blood flow reserve for the dipyridamole group was 3.6 +/- 0.4 (mean +/- 1 standard error of the mean). Real-time MCE is feasible in normal human volunteers and provides homogenous opacification of the myocardium. Furthermore, quantification of myocardial blood flow with real-time MCE in normal human beings produces results that are consistent with the known physiology of the coronary microcirculation.

A trial fibrillation (AF) is a frequent reason for emergency room visits.1 Traditional practice has been to admit patients with new AF for management.2 Despite this widespread practice pattern, the clinical utility of this approach is uncertain, as evidenced by a recent retrospective review of patients with acute, uncomplicated AF.3 A retrospective chart review was performed on all patients presenting with AF to the emergency room at a university hospital from September 1997 to November 1998, to assess the impact of a first episode of uncomplicated AF on clinical outcomes, length of stay, and actual direct costs. • • • Patients meeting the following eligibility criteria had data abstracted: (1) newly diagnosed or new onset AF; (2) uncomplicated clinical status at initial presentation, with no indication for hospital admission other than AF; (3) age between 18 and 75 years; (4) no contraindications to anticoagulation; and (5) no symptomatic congestive heart failure or known left ventricular ejection fraction ,30%. Forty-seven patients were identified. AF was confirmed in each case and the records were abstracted for baseline clinical and demographic information, clinical outcomes, medical management, length of stay, and clinical follow-up after initial presentation. Actual direct costs were calculated using the Transition Systems, Inc., cost allocation system (Eclipsys Corporation, Delray Beach, Florida). The costs of diagnostic testing (echocardiography, stress testing) related to AF after discharge performed on an outpatient basis were included. Subgroup analyses were performed based on the disposition of the patient after emergency room evaluation and on the presence or absence of spontaneous conversion of AF to sinus rhythm. Bivariate comparisons were made using Fisher’s exact test, chi-square test, or Pearson’s chi-square test, and means were compared across groups using Student’s t test. SAS version 6.2 (SAS Institute, Cary, North Carolina) was used for analyses. A p value ,0.05 was considered significant. The study group consisted of 47 patients with a mean age of 57 6 16 years (range 18 to 75). Baseline clinical and demographic characteristics are listed in Table 1. The use of rate control, anticoagulation, and resource utilization after initial presentation are shown in Table 2. The mean length of stay was 1.72 6 0.99 days (range 1 to 5) and the mean actual direct cost was $1,989 6 $1,583 dollars (range $202 to $4,430). The 25th and 75th percentiles for length of stay were 1 and 2 days, and for actual direct costs were $1,171 and $2,443. Among the 47 patients, 39 patients (83%) were admitted to the hospital and 8 patients (17%) were discharged from the emergency room. Mean age and gender ratio did not differ between the admitted paFrom the Cardiovascular Division, Washington University, St. Louis, Missouri; the Heart Care Program, Consortium for Health Outcomes, Innovation, and Cost Effectiveness Studies, and the Department of Emergency Medicine, University of Michigan Health System, Ann Arbor, Michigan. Drs. Kim and Eagle were supported by a research grant from Pharmacia-Upjohn Pharmaceuticals, Kalamazoo, Michigan. Dr. Kim’s address is: Campus Box 8086, Cardiovascular Division,Washington University in St. Louis, 660 S. Euclid Ave., St. Louis, Missouri 63110. E-mail: mkim@im.wustl.edu. Manuscript received September 14, 2000; revised manuscript received and accepted January 24, 2001. TABLE 1 Clinical Features of the Study Group (n 5 47)

ContextAcute aortic dissection is a life-threatening medical emergency associated with high rates of morbidity and mortality. Data are limited regarding the effect of recent imaging and therapeutic advances on patient care and outcomes in this setting.ObjectiveTo assess the presentation, management, and outcomes of acute aortic dissection.DesignCase series with patients enrolled between January 1996 and December 1998. Data were collected at presentation and by physician review of hospital records.SettingThe International Registry of Acute Aortic Dissection, consisting of 12 international referral centers.ParticipantsA total of 464 patients (mean age, 63 years; 65.3% male), 62.3% of whom had type A dissection.Main Outcome MeasuresPresenting history, physical findings, management, and mortality, as assessed by history and physician review of hospital records.ResultsWhile sudden onset of severe sharp pain was the single most common presenting complaint, the clinical presentation was diverse. Classic physical findings such as aortic regurgitation and pulse deficit were noted in only 31.6% and 15.1% of patients, respectively, and initial chest radiograph and electrocardiogram were frequently not helpful (no abnormalities were noted in 12.4% and 31.3% of patients, respectively). Computed tomography was the initial imaging modality used in 61.1%. Overall in-hospital mortality was 27.4%. Mortality of patients with type A dissection managed surgically was 26%; among those not receiving surgery (typically because of advanced age and comorbidity), mortality was 58%. Mortality of patients with type B dissection treated medically was 10.7%. Surgery was performed in 20% of patients with type B dissection; mortality in this group was 31.4%.ConclusionsAcute aortic dissection presents with a wide range of manifestations, and classic findings are often absent. A high clinical index of suspicion is necessary. Despite recent advances, in-hospital mortality rates remain high. Our data support the need for continued improvement in prevention, diagnosis, and management of acute aortic dissection.

Background The most efficient preoperative assessment for lung volume reduction surgery (LVRS) in patients with advanced emphysema is undefined. This study analyzed the preoperative assessment of patients by surface echocardiography (without and with dobutamine infusion), the results of which were used to exclude patients with significant pre-existing cardiac disease, a contraindication to LVRS, from the surgery. Setting A university-based, tertiary care referral center. Methods Patients with emphysema who met initial LVRS screening criteria underwent resting and stress surface echocardiography with Doppler imaging. Patients were evaluated prospectively for perioperative cardiac complications. Results Between July 1994 and December 1996, 503 candidates for LVRS were evaluated. Of these, 207 patients (81.8%) who had echocardiography performed at our institution formed the primary study group. Images were adequate for the analysis of chamber sizes and function in 206 patients (99.5%) undergoing resting echocardiography, and the images were adequate for wall motion analysis in 172 of 174 patients (98.9%) undergoing functional testing. Right heart abnormalities were common (40.1%). Significant pulmonary hypertension (> 35 mm Hg) was uncommon (5 patients, 5.4%) among the 92 patients who subsequently underwent right heart catheterization. Occult ischemia, left ventricular dysfunction, and valvular abnormalities also were uncommon. Thus, although Doppler imaging estimates of right ventricular systolic pressure were imperfect, echocardiographic findings of normal right heart anatomy and function excluded significant pulmonary hypertension. Ninety patients (43%) eventually underwent LVRS (70 bilateral and 20 unilateral). A total of 13 perioperative cardiac events occurred in 10 patients, 6 of whom had undergone preoperative echocardiography. No patient suffered acute myocardial infarction or cardiac death. Conclusions: Despite potential limitations due to severe obstructive lung disease, surface echocardiographic imaging is a feasible, noninvasive tool in this patient population to identify patients with evidence of cor pulmonale that suggests pulmonary hypertension. The routine use of surface resting and stress echocardiography for preoperative screening obviates the need for invasive right heart catheterization in many patients and results in a low incidence of significant perioperative cardiac complications.

In a randomized, controlled clinical trial, we evaluated the ability of an algorithm to identify, before peak stress, patients who will ultimately require atropine during dobutamine stress echocardiography. The effects of early atropine administration on test duration, atropine dose, dobutamine dose, and heart rate response also were studied. Compared with conventional atropine administration at peak dobutamine infusion, early atropine administration reduced test duration 8% (1.1 minutes, p = 0.02) and total dobutamine use 11% (0.41 mg/kg, p = 0.02) but required 90% more atropine (0.36 mg, p0.001). Conventional atropine administration resulted in a late, rapid rise in both heart rate and rate-pressure product. However, the heart rate and rate-pressure product curves for patients receiving early atropine paralleled those seen in patients not requiring atropine during dobutamine stress echocardiography. In conclusion, early atropine administration provides a more balanced stress and reduces test duration, thus decreasing total exposure to dobutamine and potentially increasing test efficiency.

Changes in left atrial (LA) appendage pulsed-wave Doppler velocities and changes in grades of spontaneous contrast occur immediately after electrical cardioversion of atrial fibrillation (AF) using transesophageal echocardiography (TEE). The effect of sequential ineffective electrical cardioversion attempts or chemical cardioversion on these parameters is unknown. TEE was performed in 23 patients with chronic AF. Doppler velocities and grades of spontaneous contrast were assessed before and after each cardioversion attempt until sinus rhythm was achieved. Doppler emptying and filling velocities were significantly decreased after electrical (0.39 +/- 0.14 vs 0.27 +/- 0.16 [p = 0.01] and 0.43 +/- 0. 18 vs 0.30 +/- 0.14 m/s [p = 0.01]) or chemical cardioversion to sinus rhythm (0.65 +/- 0.18 vs 0.31 +/- 0.06 [p = 0.03] and 0.64 +/- 0.22 vs 0.44 +/- 0.17 m/s [p = 0.04]). Spontaneous contrast developed in 1 of 3 patients after chemical conversion to sinus rhythm and was present in 11 of 20 patients before electrical cardioversion, developing in 4 patients and intensifying in 2 patients immediately after successful cardioversion. These phenomena were not seen after ineffective electrical or chemical cardioversion attempts. This suggests that restoration of sinus rhythm is in itself responsible for these phenomena, not the method by which sinus rhythm is achieved.

Orthotopic liver transplantation is an established therapy for end-stage liver disease. This study evaluated the range of cardiovascular abnormalities in patients undergoing evaluation for orthotopic liver transplantation and determined the prognostic implications of abnormal echocardiographic features, including ischemia during dobutamine stress echocardiography, in predicting postoperative cardiac events. Two-dimensional echocardiography was performed in 190 patients for assessment of left ventricular function, valvular pathology, and pulmonary hypertension. Dobutamine stress echocardiography was performed in 165 patients for evaluation of inducible ischemia. Contrast echocardiography for detection of intrapulmonary shunting was performed in 125 patients at rest and in 99 during dobutamine stress. Left ventricular dysfunction, significant valvular regurgitation, and inducible ischemia were identified in

Myocardial contrast echocardiography is useful for the assessment of myocardial perfusion but has required direct intracoronary injections. Aortic root myocardial contrast echocardiography has the potential advantage of allowing simultaneous assessment of multiple perfusion beds, as well as evaluating competitive and collateral flows. This study assessed the safety and efficacy of intracoronary and aortic root injections of sonicated 5% human serum albumin (Albunex) with and without concomitant coronary vasodilation. Without vasodilation, 72% of intracoronary injections had optimal myocardial enhancement, compared with 21% of aortic root injections. For individual patients, significant dose-response relationships existed for both intracoronary and aortic root injections, although contrast intensity for a given dose varied between patients. Pharmacologic vasodilation resulted in significant increases in contrast intensity and in the incidence of optimal myocardial contrast after aortic root injections. Aortic root myocardial contrast echocardiography potentially allows the simultaneous assessment of multiple perfusion beds through a route somewhat less invasive than that of direct intracoronary injections.

Albunex is an intravenous contrast agent that opacifies the left ventricle (LV). This study evaluated the effect of Albunex on the enhancement of LV endocardial border localization during dobutamine stress echocardiography (DSE). Albunex was infused in 30 patients at baseline and with low- and high-dosage dobutamine. Apical two- and four-chamber views were divided into six segments each, and enhancement of LV border localization was compared with precontrast images graded as follows: 0 = none; 1 = faint; or 2 = optimal. The mean grade and percentage of segments with optimal localization of LV endocardial borders were determined. There was a significant increase in enhancement with low- and high-dosage dobutamine when compared with baseline. Of 179 segments with suboptimal enhancement at baseline, 137 (77%) became optimal during DSE with Albunex. We conclude that Albunex improves localization of LV endocardial borders and that this localization is enhanced during DSE.

The cardiovascular evaluation of patients with end-stage renal disease (ESRD) has been hampered by the suboptimal sensitivity and specificity of currently employed diagnostic tests. Dobutamine stress echocardiography (DSE) is a recently developed technique which is accurate for the diagnosis of coronary artery disease (CAD) in general populations. The purpose of this study was to assess its diagnostic accuracy and prognostic implications in patients with ESRD. Patients with ESRD (n = 97) underwent DSE as part of a preoperative evaluation before being listed for renal transplantation. Patients were followed for 12 +/- 6 months (range 1 to 24) after the study. Rest and dobutamine stress echocardiograms were analyzed for regional and global function. Coronary angiography was performed in 30 patients, and 25 underwent renal transplantation in the follow-up period. DSE had a sensitivity of 95% (92% for 1-vessel, 100% foror = 2-vessel disease), specificity of 86%, and accuracy of 90% for the detection of CAD. During the follow-up period, 6 patients died; DSE revealed inducible ischemia in 4, and catheterization before death revealed multivessel CAD in 2. Conversely, a normal DSE identified a very low risk population, with a 97% probability of being free of cardiac complications or death during the follow-up period. We conclude that DSE accurately identifies CAD in patients with ESRD and identifies a cohort of patients at low risk for cardiac complications.

Studies assessing dobutamine stress (DS) echocardiograpphy (echo) have included 12-lead electrocardiograms (ECG) in their protocol. We retrospectively reviewed the records of 76 patients who were referred for DS echo and coronary angiography to assess the incremental diagnostic value of DS ECG beyond the results of the echocardiographic images of the DS echo. The prevalence of coronary artery disease was 86%. Baseline ST-segment abnormalities prohibited assessment of ischemic ST-segment changes in 35 (46%) patients. For the detection of a ≥50% stenosis on coronary angiography, DS echo alone had a sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of 92%, 73%, 95%, 62%, and 89%, respectively. The DS ECG alone had a sensitivity, specificity, PPV, NPV, and accuracy of 38%, 45%, 81%, 11%, and 39%, respectively. Combined results of the DS echo and the DS ECG slightly increased sensitivity, but with a marked reduction in specificity, PPV, NPV, and accuray. We conclude that (1) DS ECG is interpretable for ischemic ST-segment changes in about 50% of patients referred for DS echo; (2) DS ECG is a poor predictor of coronary artery disease; and (3) DS ECG response only slightly increases the sensitivity of the echo findings of a DS echo study. Because the incremental diagnostic value of the DS ECG response is poor, elimination of the 12-lead DS ECG is unlikely to diminish the diagnostic value of the DS echo and may result in a substantial cost savings.