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Transcatheter aortic valve replacement is a major advance that has dramatically changed our approach to elderly patients with severe aortic stenosis. This advance has been made possible by innovative device and delivery improvements, coupled with rapid developments in multimodality imaging. Multimodality imaging draws from multiple imaging fields and is central to patient evaluation and treatment. The primary modalities to date include transthoracic echocardiography and transesophageal echocardiography, computed tomography, and fluoroscopy. Each of these modalities carries a different weight in the various stages of patient selection, procedural guidance, monitoring, and follow-up. Multimodality imaging ensures optimal device selection, delivery, and patient safety, and will continue to advance as the next generation of aortic valve devices further advance cardiovascular care.

MISSION: To advocate for accessible, highest quality, cost-effective cardiovascular care for Californians. The purpose of the Chapter shall be to contribute to the prevention of cardiovascular diseases, to ensure optimal quality care for the individuals with such diseases, and to foster the highest professional ethical standards.

Aims: Percutaneous repair of mitral regurgitation (MR) by leaflet apposition using a clip deployed via transseptal catheterisation is undergoing evaluation., Methods and Results: In order to detect the potential for clinically significant left ventricular inflow obstruction after percutaneous repair, we measured mitral valve area (MVA) and mean transmitral gradient (MVG) echocardiographically in 96 patients implanted with a clip followed for up to 24 months. By planimetry, the mean MVA decreased from 6.0 +/- 1.3 cm2 to 3.6 +/- 1.2 cm2 (p < 0.05) (range 1.9 to 7.6 cm2) after clip placement, and remained unchanged after 24 months of follow-up (3.5 +/- 0.8 cm2). The mean MVG increased after clip placement from 1.7 +/- 0.9 mmHg to 4.1 +/- 2.2 mmHg (p < 0.05), and did not increase further to 24 months (3.8 +/- 1.9 mmHg). There were no differences in MVA or MVG between patients who received 1-clip (69%) and those receiving 2-clips (31%). Patients with functional MR (23%) had a slightly smaller MVA, both at baseline and after clip placement, but did not differ from degenerative MR patients at later follow-up. After 2 years of follow-up, no patient required surgery for LV inflow obstruction., Conclusions: Mitral repair with the MitraClip device for MR decreases MVA without significant mitral obstruction. After 2 years of follow-up, no patient required surgery for LV inflow obstruction, and these results were not influenced by the use of more than 1 clip or the aetiology of MR.

As presented previously in Part 1 of this 2-part article, many long-term clinical trials provide overwhelming evidence of the benefits of angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) across the cardiovascular continuum. Trials also indicate additive or synergistic effects of combination therapy in renal disease and heart failure. Part 2, which is presented here, discusses the extensive interaction of the renin-angiotensin system (RAS) with the cellular and molecular pathophysiology of cardiovascular disease and the cross-continuum effects of ARBs and ACE inhibitors, which raises the possibility that RAS inhibition can offer protection in high-risk patients who do not have symptoms. Although trial evidence supports the effectiveness of monotherapy, the benefits of combined ACE inhibitor/ARB therapy in high-risk patients await confirmation. Ongoing clinical research will provide new and important information regarding the efficacy of specific combination (ACE inhibitor/ARB) therapies., (2008 Le Jacq.)

Cardiovascular disease is understood as a continuum; risk factors induce a pathophysiologic cascade that culminates in end-organ failure. The renin-angiotensin system (RAS) influences multiple aspects of the pathophysiology via hemodynamic and nonhemodynamic effects. Many long-term clinical trials provide overwhelming evidence of benefits of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) across the cardiovascular continuum, including benefits regarding hypertension, myocardial infarction, stroke, renal disease, and heart failure. Trials also indicate additive or synergistic effects of combination therapy in renal disease and heart failure, a possibility supported by the basic biochemistry of the agents. Discussion of these trials is included in part 1 of this 2-part review. Part 2 of the review will discuss the extensive interaction of the RAS with the cellular and molecular pathophysiology of cardiovascular disease and the cross-continuum effects of ARBs and ACE inhibitors, which raise the possibility that RAS inhibition can offer protection in high-risk patients who do not have symptoms. The benefits of combined ACE inhibitor/ARB therapy in high-risk patients await confirmation; ongoing clinical research in this area will be discussed.

The systemic circulation to the lung supplies the trachea and airway walls and may be important in the pathophysiology of asthma and pulmonary oedema. An understanding of the venous drainage pathways of this bronchial blood flow may be therapeutically important. The purpose of this study was to understand the normal drainage pathways in sheep. In seven anaesthetized, ventilated sheep we injected echo contrast agents into a systemic vein or into the bronchial artery while performing echocardiography to determine whether the drainage could be observed to the right heart and/or to the left heart. During transoesophageal echo (n=5) or heart surface echo (n=2), cephalic vein injection of <8 microm diameter gelatin microballoons promptly opacified the right but never the left-sided circulation. Air in agitated saline in the seven animals showed the same result. By contrast, injection into the bronchial artery promptly opacified the left atrium, left ventricle, and aorta but not the right-sided circulation in all seven microballoon injections and all but one of the air in agitated saline injections. The failure of the echo agents to pass through the pulmonary circulation may be related to sheep pulmonary intravascular macrophages or the surface forces on air bubbles of small size promoting collapse. The main conclusion is that there are bronchopulmonary anastomoses that connect the bronchial circulation to the pulmonary venous circulation connecting distal to the pulmonary capillaries. Any bronchial venous drainage to the right-sided circulation must have been below the detection level of the instruments and would in any case appear to be much less that the post-pulmonary capillary anastomoses noted. Pulmonary venous hypertension would be expected to have a direct effect on the bronchial circulation.

The authors reviewed all negative preoperative dobutamine stress echocardiograms (DSEs) performed over a 3-year period to determine the value of negative DSE for preoperative risk assessment in elderly patients. All patients with negative DSE performed for preoperative evaluation were followed. Cardiac event rates during and after the operative procedure were determined for hard end points (nonfatal myocardial infarction, cardiac death) and soft end points (emergency room visits, hospitalization for unstable angina, congestive heart failure, coronary angioplasty, coronary artery bypass graft surgery). Results noted that DSEs were negative for ischemia in 82 preoperative evaluations. Group 1 (age >/=65; n=41) had hard and soft event rates per patient/year of 0.97% and 7.3%, while group 2 (age <65; n=41) had hard and soft event rates per patient/year of 0.81% and 10.8%. There were no significant differences in event rates between the two groups (p=NS). In conclusion, the authors found that negative DSEs predict low cardiac event rates in elderly patients during the perioperative and long-term postoperative periods, which are not significantly different from the cardiac event rates in a younger cohort., (Copyright 2003 Le Jacq Communications, Inc.)

Objective: To determine the value of contrast echocardiographic studies in patients admitted to ICUs who have poor echocardiographic windows secondary to COPD, ventilator use, or inability to obtain optimal positioning for the echocardiogram., Design: A prospective comparison study of technically difficult patients in the ICU., Outcome Measure: The total scores for the left ventricle (LV) in the two-chamber and four-chamber views were calculated at baseline and following injection of 1 to 2 mL of a contrast agent. The mean numbers of segments visualized in all patients at baseline and after injection of contrast agent were compared to assess the effect on improved visualization., Results: Forty consecutive patients underwent echocardiography in the ICU for evaluation of LV function. Of these, 25 patients (63%) had poor visualization of the endocardium and required IV contrast agent. In these 25 patients, the average baseline segmental score was 4.5, compared to 11.6 in patients who received an IV contrast agent. Nineteen patients had an average baseline segmental score of 3.9 and were deemed to have a nondiagnostic study. After administration of IV contrast, all patients converted to a diagnostic study, with an average score of 11.6 segments visualized., Conclusions: Use of echocardiographic contrast agents in selected patients with poor baseline echocardiographic windows in the ICU setting significantly enhances segmental LV visualization and yielded 100% conversion from nondiagnostic to diagnostic studies.

Background: Ultrasound (US) at low frequencies has been shown to enhance clot lysis by itself and in the presence of urokinase (UK). The comparative effects of air-filled versus perfluorocarbon-filled polymer bispheres in enhancing this effect have not been previously demonstrated., Methods: Freshly drawn human blood was incubated at 37 degrees C for 2 hours, and the subsequent formed clot was dried and weighed. It was then exposed to saline control, saline + UK (10,000 IU), saline + UK + US, saline + UK + US + low shell-strength polymer bispheres (PB1), saline + UK + US + high shell-strength polymer bispheres (PB2), and perfluorocarbon-filled high shell-strength polymer bipsheres (PB3) for a total of 6 minutes. Clots were removed and weighed to determine the percentage of thrombolysis., Results: The percentage of clot lysis for each study group was as follows: saline 18.5% +/- 4%, US alone 22.2% +/- 5%, UK alone 21.9% +/- 4%, US+UK 32.2% +/- 8% (P <.05 compared with UK alone), US+UK+PB1 36.9% +/- 8%, US+UK+PB2 34.3% +/- 8%, and US+UK+PB3 45.0% +/- 11% (P <.05 compared with US+UK, P <.05 compared with US+UK+PB2)., Conclusion: Ultrasound at 20 kHz significantly enhances clot lysis. The addition of perfluorocarbon-filled bispheres increased this effect more significantly than did the addition of air-filled polymer bispheres.

The aim of this study was to assess the prognostic value of the 12-lead electrocardiogram (ECG) obtained during dobutamine stress echocardiography (DSE) in predicting subsequent cardiac events. We retrospectively analyzed 345 patients undergoing DSE in 1992-1994 and selected those patients with negative echo results for ischemia. Of the 200 patients with negative DSE results, a separate analysis of their ECG data was performed with results reported as either positive, negative, or nondiagnostic for ischemia. Follow-up was performed through a physician chart review and direct telephone contact. Event rates were determined for hard (myocardial infarction or cardiac death) and soft (hospitalization for angina and/or congestive heart failure, coronary angioplasty, or coronary artery bypass graft surgery) cardiac events occurring after the negative DSE for up to 6 years after the test. Death was also determined by referencing the patients' data with mortality data available on the Internet. There were 143 patients with ECG data reported as negative and 40 patients with ECG data reported as positive for ischemia. The hard and soft event rates were 1.5% and 9% per patient per year in the ECG negative group and 2% and 11% in the ECG positive group. There were no statistical differences in event rates between the two groups during the 5-year follow-up period. Our results suggest that the ECG result obtained during DSE does not confer any incremental prognostic value over the echo result.

Background: Mild hypotension (drops of systolic blood pressure of > or = 20 mmHg) occurs in 14-38% of dobutamine stress echo (DSE) and carries a good prognosis for subsequent cardiac events. The incidence and significance of more profound hypotension (PH) (> or = 50 mmHg) is unknown., Hypothesis: The aim of the study was to determine the incidence of PH during DSE and its prognosis for subsequent cardiac events., Methods: We reviewed 617 DSE performed at our institution between 1992 and 1996 and identified two DSE subgroups. The first group (PH group) consisted of all patients with PH during DSE. A second group was selected with baseline characteristics similar to the PH group but without PH during DSE (non-PH group). Follow-up was by a physician chart review and direct telephone contact. Cardiac event rates were determined for hard [myocardial infarction (MI), or cardiac death] and soft (angina, congestive heart failure, coronary angioplasty, or coronary bypass surgery) events occurring after the DSE., Results: Of the 617 DSE performed, 16 (3%) patients developed PH (PH group) during DSE, with 13 showing no inducible ischemia. The hard and soft cardiac event rate in this 13 PH group was 46% (mean follow-up of 28.7 +/- 18 months). Of the non-PH group, 32 patients had a negative DSE with a coronary event rate of 12.5%. Profound hypotension correlated with a significantly higher cardiac event rate (p < 0.02)., Conclusions: The incidence of PH during DSE is low (3%) and appears to predict a worse prognosis for subsequent cardiac events.

Acute myocardial infarction as a complication of dobutamine stress echocardiography (DSE) is described in two patients during or shortly after undergoing the procedure. Both clinical events resulted in characteristic elevations in cardiac enzymes and the development of new electrocardiographic Q waves in the inferior leads. Subsequent coronary angiography was performed in both cases; one patient required two-vessel coronary artery bypass grafting to his first obtuse marginal and posterior descending arteries, and the other underwent successful angioplasty of an occluded proximal right coronary artery. Only two cases of DSE-associated myocardial infarction have been reported previously in the literature.

The purpose of this study was to evaluate the sensitivity of current echocardiographic criteria in detecting cardiac tamponade in the patient who has undergone cardiovascular surgery. Because the current echocardiographic criteria for tamponade were initially developed and studied predominantly in patients with medical problems, relatively less information is available in patients who have undergone cardiac surgery. Of 848 consecutive patients who underwent cardiovascular surgery, patients were selected for the study if they had clinical or hemodynamic deterioration and had undergone an echocardiogram just before a successful pericardiocentesis or a surgical evacuation of pericardial blood or clot. The echocardiograms were evaluated for evidence of chamber collapse, cardiac motion, Doppler flow variations, and the location and width of pericardial separation. Fourteen patients were identified who met the inclusion criteria (clinical or hemodynamic deterioration, recent echocardiogram, and successful intervention) for cardiac tamponade. The clinical and hemodynamic findings were hypotension (13 patients), low cardiac output (7), low urine output (3), cardiopulmonary arrest (1), elevated central venous pressure (1), and shortness of breath (1). In these patients current echocardiographic criteria were seen infrequently: chamber collapse in the right atrium (6 of 14 patients) and right ventricle (4 of 14); Doppler flow variation (2 of 5); and swinging heart (0 of 15), whereas increased pericardial separation (> or = 10 mm) was seen in all (14 of 14) the patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Background: Left ventricular (LV) hypertrophy, as measured by M-mode echocardiography, is an independent predictor of mortality and/or morbidity from coronary heart disease (CHD). LV global and segmental systolic dysfunction also have been associated with myocardial ischemia and cardiovascular morbidity and mortality. Echocardiographic data, especially two-dimensional, have not been available previously from multicenter-based studies of the elderly. This report describes the distribution and relation at baseline of echocardiographic LV mass and global and segmental LV wall motion to age, sex, and clinical disease category in the Cardiovascular Health Study (CHS), a cohort of 5201 men and women (4850 white) 65 years of age and older., Methods and Results: M-mode LV mass adjusted for body weight increased modestly with age (P < .0001), increasing less than one gram per year increase in age for both men and women. After adjustment for weight, LV mass was significantly greater in men than in women and in participants with clinical CHD compared with participants with neither clinical heart disease nor hypertension (both P < .001). Across all CHS age subgroups, the difference in weight-adjusted LV mass by sex was greater in magnitude than the difference related to clinical CHD. M-mode measurements of LV mass could not be made in 34% of CHS participants, and this was highly related to age (29% in the 65 to 69 year versus 50% in the 85+ year age group, P < .001) and other risk factors. In participants with clinical CHD and with neither clinical heart disease nor hypertension, LV ejection fraction and segmental wall motion abnormalities were more prevalent in men than women (all P < .001). Of interest, 0.5% of men and 0.4% of women with neither clinical heart disease nor hypertension had LV segmental wall motion abnormalities, suggesting silent disease, compared with 26% of men and 10% of women in the clinical CHD group (P < .0001). Multivariate analyses revealed male sex and presence of clinical CHD (both P < .001) to be independent predictors of LV akinesis or dyskinesis., Conclusions: Significant baseline relations were detected between differences in sex, prevalent disease status, and echocardiographic measurements of LV mass and systolic function in the CHS cohort. Age was weakly associated with LV mass measurements and LV ejection fraction abnormalities. These relations should be considered in evaluating the preclinical and clinical effects of CHD risk factors in the elderly.

Background: Milrinone, a phosphodiesterase inhibitor, enhances cardiac contractility by increasing intracellular levels of cyclic AMP, but the long-term effect of this type of positive inotropic agent on the survival of patients with chronic heart failure has not been determined., Methods: We randomly assigned 1,088 patients with severe chronic heart failure (New York Heart Association class III or IV) and advanced left ventricular dysfunction to double-blind treatment with (40 mg of oral milrinone daily (561 patients) or placebo (527 patients). In addition, all patients received conventional therapy with digoxin, diuretics, and a converting-enzyme inhibitor throughout the trial. The median period of follow-up was 6.1 months (range, 1 day to 20 months)., Results: As compared with placebo, milrinone therapy was associated with a 28 percent increase in mortality from all causes (95 percent confidence interval, 1 to 61 percent; P = 0.038) and a 34 percent increase in cardiovascular mortality (95 percent confidence interval, 6 to 69 percent; P = 0.016). The adverse effect of milrinone was greatest in patients with the most severe symptoms (New York Heart Association class IV), who had a 53 percent increase in mortality (95 percent confidence interval, 13 to 107 percent; P = 0.006). Milrinone did not have a beneficial effect on the survival of any subgroup. Patients treated with milrinone had more hospitalizations (44 vs. 39 percent, P = 0.041), were withdrawn from double-blind therapy more frequently (12.7 vs. 8.7 percent, P = 0.041), and had serious adverse cardiovascular reactions, including hypotension (P = 0.006) and syncope (P = 0.002), more often than the patients given placebo., Conclusions: Our findings indicate that despite its beneficial hemodynamic actions, long-term therapy with oral milrinone increases the morbidity and mortality of patients with severe chronic heart failure. The mechanism by which the drug exerts its deleterious effects is unknown.

The pathoanatomy and factors associated with transient mitral regurgitation (MR) induced by myocardial ischemic stress are unknown. Changes in valvular and ventricular parameters during transient, stress-induced MR in patients with coronary artery disease were investigated, and the clinical characteristics of these patients were identified. Color flow Doppler echocardiography was used to quantify the MR color area, the coaptation point of the mitral leaflets, the mitral valve anulus diameter, and left ventricular volumes and wall motion in 42 patients before and immediately after exercise echocardiography (group 1, n = 27), or before and during percutaneous transluminal coronary angioplasty (PTCA) (group 2, n = 15). Of the 27 patients with exercise echocardiography, 4 developed new, transient MR (group 1B) and 9 had MR both at rest and during exercise (group 1C). Of the 15 patients with PTCA, 7 developed new MR (group 2B). New MR (groups 1B and 2B) was associated with more severe stress-induced ventricular dyskinesia (p less than 0.05) than was seen in patients with chronic MR (group 1C) or in patients without MR, and occurred predominantly in patients with left anterior descending or right coronary artery stenoses. Stress-induced MR was not associated with changes in blood pressure or in mitral valve anulus diameter, nor with the development of mitral valve prolapse. It was associated with apical displacement of the mitral leaflets in patients in group 1B and C (p less than 0.05). New MR flow areas were significantly smaller than those in patients with chronic MR (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Elective cardioversion was undertaken in a patient with a VVI pacemaker and atrial tachyarrhythmia after converting the pacemaker to a VOO mode of function. The cardioverter output energy was unwittingly synchronized to the pacemaker output pulses that were falling randomly in various portions of the cardiac cycle. This resulted in the cardioverter DC shock being discharged in the ST segment of the native QRS with consequent ventricular fibrillation.

The results of a survey of 363 physicians performing echocardiography were evaluated to assess the relative safety of contrast echocardiography. Fifteen physicians reported a variety of transient side effects, including neurologic and respiratory symptoms. Although contrast echocardiography appeared to carry some risk for side effects, that risk was low (0.062%) and no residual side effects or complications were observed. In view of the significant benefits reported for contrast echocardiography, it appears to remain a valuable technique that is safer than currently available alternative diagnostic modalities. However, during contrast echocardiography, precautions should be taken to prevent the injection of visible amounts of air, especially in patients with a right to left shunt or arterial catheters.

The 6-month extended vasodilator efficacy of the oral angiotensin converting enzyme (ACE) inhibitor, captopril (CPT), was evaluated by sequential cardiac catheterization, nuclear scintigraphy, echocardiography, treadmill exercise, and symptomatology in nine patients with severe chronic left ventricular (LV) failure (CHF). CPT lowered LV filling pressure (from 23 to 14 mm Hg acutely (p less than 0.001) and to 14 mm Hg (p less than 0.01) with continuous 6-month therapy; concomitantly CPT raised cardiac index from 2.03 to 2.46 L/min/m2 initially (p less than 0.02) and to 2.33 L/min/m2 (p less than 0.02) at 6 months. Simultaneously CPT raised LV ejection fraction from 0.21 to 0.25 acutely (p less than 0.01) and to 0.30 (p less than 0.001) and to 60 mm (p less than 0.001) at 6 months. These beneficial actions of CPT on LV pump function raised treadmill exercise duration (from 339 to 426 seconds initially (p less than 0.05) and to 499 seconds (p less than 0.05) at 6 months, while considerably reducing CHF symptomatology (p less than 0.001). Thus ACE inhibition by CPT provides markedly beneficial sustained hemodynamic and clinical improvement in advanced LV failure without fluid accumulation or late vasodilator drug tolerance.

To evaluate the effectiveness of oral vasodilator therapy in chronic congestive heart failure, 20 mg of isosorbide dinitrate or placebo was administered orally in double-blind fashion to 25 patients with congestive heart failure. In 15 patients receiving isosorbide dinitrate, pulmonary arterial wedge pressure decreased 5 minutes to 5 hours after drug administration; the peak reduction was observed at 1 hour (from 23 to 14 mm Hg; P less than 0.001). Wedge pressure decreased to normal (12 mm Hg or less) in 8 of the 15 patients (Group I) but remained greater than 12 mm Hg in 7 (Group II). Reductions in mean systemic arterial pressure, systemic vascular resistance and pressure-time per minute also occurred. Indexes of pump output were unchanged in the 15 who received isosorbide dinitrate but tended to decrease slightly in Group I. Stroke index (from 23 to 26 cc/m2) and stroke work index (from 21.4 to 24.1 g-m/m2) increased slightly but significantly (P less than 0.05) in Group II. Thus the prinicpal hemodynamic action of isorbide dinitrate is marked and sustained reduction in left ventricular filling pressure without pronounced effect on cardiac output. This agent should be used in congestive heart failure primarily for relief of congestive symptoms.

Laser energies can be transmitted through flexible optical fiber to vaporize and penetrate coronary atherosclerotic and thrombotic obstructions. There are risks and complications involved in this therapy, however, including perforation, aneurysm formation, and thromboembolic risks, and further research is needed to render the laser recanalization procedure safe.

We examined the potential for laser irradiation of congenital heart defects, with the use of postmortem hearts and an argon ion laser with a flexible quartz fiber. Atrial septectomy was performed in five newborn hearts. Obstructive lesions were relieved by laser irradiation in valvular pulmonic and aortic stenosis, dysplastic pulmonary valve, pulmonary atresia, and coarctation of the aorta. To demonstrate the efficacy of in vivo cardiac laser surgery, atrial septectomy was also performed in an anesthetized dog model, under echocardiographic visualization, without change in heart rate or blood pressure. Our results demonstrate the feasibility of intracardiac and intravascular laser irradiation for palliation and repair of selected congenital heart diseases.