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Up to 10% of patients with atrial fibrillation (AF) undergo percutaneous coronary intervention (PCI). A systematic review and network meta-analysis were conducted by searching PubMed, Embase, and the Cochrane database of systematic reviews for randomized control trials that studied the safety and efficacy of different antithrombotic strategies in these patients. Six studies, including 12,158 patients were included. Compared to that in the triple antithrombotic therapy group (vitamin K antagonist (VKA) plus P2Y12 inhibitor and aspirin), thrombolysis in myocardial infarction (TIMI) major bleeding was significantly reduced in the dual antithrombotic therapy (non-vitamin K oral anticoagulants (NOACs) plus P2Y12 inhibitor) group by 47% (Odds ratio (OR), 0.53, 95% credible interval [CrI], 0.35&ndash, 0.78, I2 = 0%). Besides, NOAC plus a P2Y12 inhibitor was associated with less intracranial hemorrhage compared to VKA plus single antiplatelet therapy (OR: 0.20, 95% CrI: 0.05&ndash, 0.77). There was no significant difference in the trial-defined major adverse cardiac events or the individual outcomes of all-cause mortality, cardiovascular death, myocardial infarction, stroke or stent thrombosis among all antithrombotic strategies. In conclusion, antithrombotic strategy of NOACs plus P2Y12 inhibitor is safer than, and as effective as, the strategies including aspirin when used in AF patients undergoing PCI.

A 55-year-old man underwent successful percutaneous coronary intervention for the middle left circumflex artery with a 3.5 × 28-mm bioresorbable vascular scaffold (BVS). At 18 months, follow-up coronary angiography showed ectatic change with aneurysm formation over the BVS. Optical coherence tomography revealed absence of strut continuity at the aneurysm site, in the middle of the BVS. A literature review identified nine patients with intrascaffold aneurysm, including the present patient, which developed 6-32 months after BVS implantation. Of these nine patients, four underwent percutaneous coronary intervention for chronic total occlusion. The pathogenesis of coronary artery aneurysm is multifactorial. Most patients receive no further intervention, but long-term dual antiplatelet therapy is sometimes prescribed in conjunction with regular follow-up. © 2017 Wiley Periodicals, Inc.

Background Little information is available in Asia about the real-world practice of dual antiplatelet therapy (DAPT) duration for acute coronary syndrome (ACS) and its influence on clinical outcomes.Methods and Results:The Taiwan ACS STENT Registry was a prospective, multicenter study to observe ACS patients using clopidogrel-based DAPT after percutaneous coronary intervention (PCI). The primary outcome was a composite of cardiovascular death, myocardial infarction, and stroke. Overall, 2,221 ACS patients (62 years, 83% men) were included. DAPT duration was ≤9 months in 935 (42.1%). The incidence of primary outcome was higher in patients receiving DAPT ≤9 months compared with those receiving DAPT >9 months at 1 year (3.5% vs. 1.6%, P=0.0026). The incidence of stent thrombosis (overall 0.5%) was similar between groups. Multivariable analysis showed that DAPT >9 months was associated with a significantly lower risk of primary outcome (odds ratio 0.725, 95% confidence interval 0.545-0.965). Conclusions Our data showed that short duration of DAPT (≤9 months) was common (42.1%) in Taiwan for ACS patients undergoing PCI. DAPT ≤9 months increased the risk of the primary outcome.

Patient Initials or Identifier Number Mr. L ### Relevant Clinical History and Physical Exam A 57-year-old male with a history of Hypertension, Type II Diabetes mellitus, Dyslipidemia and Coronary artery disease, triple vessel disease status post-percutaneous coronary intervention (PCI) with a

Aims To investigate whether renal dysfunction is a useful predictor of postoperative atrial fibrillation (POAF) after cardiac surgery. We also aimed to determine whether the addition of renal dysfunction into the scoring system could improve diagnostic accuracy of the CHA2DS2-VASc score to predict POAF. Methods and results The study prospectively enrolled 350 consecutive patients who underwent cardiac surgery. Echocardiography was performed before cardiac surgery. Renal dysfunction was defined as estimated glomerular filtration rate < 60 mL min−1 1.73 m−2. All patients were monitored with continuous electrocardiographic telemetry for the occurrence of POAF until the day of hospital dismissal. Postoperative atrial fibrillation occurred in 103 of 350 patients (29%). Patients with POAF was associated with longer intensive care unit stay compared with those without POAF (3.7 ± 2.2 vs. 3.1 ± 1.4 days, P = 0.002). Both the CHA2DS2-VASc score and renal dysfunction were independent predictors of POAF in multivariate analysis. Renal dysfunction can further stratify patients with a CHA2DS2-VASc score of 0 or 1 into two groups with different POAF rates (3.1% vs. 68.8%, P < 0.001). A new scoring system (R-CHA2DS2-VASc score) derived by assigning an additional point representing renal dysfunction to the CHA2DS2-VASc score could improve its predictive accuracy. The area under the receiver operating characteristic curve increased from 0.68 to 0.71 ( P < 0.001). Furthermore, the rate of left ventricular diastolic dysfunction also increased with increasing renal dysfunction. Conclusion Renal dysfunction, associated with left ventricular diastolic dysfunction, was a significant risk factor for POAF after cardiac surgery and may improve the diagnostic accuracy of the CHA2DS2-VASc score.

Aims/Introduction Admission hyperglycemia is associated with poor outcome in patients with myocardial infarction. The present study evaluated the relationship between admission glucose level and other clinical variables in patients with ST‐elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI). Materials and Methods The 959 consecutive STEMI patients undergoing primary PCI were divided into five groups based on admission glucose levels of

Background: Renal dysfunction is associated with a higher rate of atrial fibrillation in clinical practice. This study investigated the associations between renal function, left ventricular (LV) diastolic dysfunction, and postoperative atrial fibrillation (POAF). Methods and Results: A total of 265 consecutive patients who underwent cardiac surgery were prospectively enrolled in the study. Echocardiography was performed before cardiac surgery. The patients were divided into 3 groups based on estimated glomerular filtration rate (eGFR) (group 1, ≥90ml·min–1·1.73m–2; group 2, 60–90ml·min–1·1.73m–2; and group 3, 15 – also increased (group 1, 19.0%; group 2, 38.1%; and group 3, 48.3%; P

Background/Purpose Percutaneous coronary intervention (PCI) has been increasingly adopted for unprotected left main coronary artery (LMCA) disease. The aim of this study was to evaluate the predictors of long-term clinical outcomes in patients after elective stent implantation for unprotected LMCA disease. Methods A total of 122 patients with medically refractory angina who received coronary stenting for unprotected LMCA disease between August 1997 and December 2008 were included. Results During the follow-up period of 45 ± 35 months (range: 1–137 months), the incidence of repeated PCI and/or coronary artery bypass grafting (CABG), and cardiovascular and total mortality were 28% (34 patients), 20% (24 patients), and 25% (31 patients), respectively. Multivariate analysis revealed that young age [ p = 0.02; hazard ratio (HR): 2.19, 95% confidence interval (CI): 1.11–4.30] and bare-metal stent (BMS) use ( p = 0.02; HR: 5.35, 95% CI: 1.27–22.57) were the independent predictors of repeated PCI and/or CABG. Only lower left ventricular ejection fraction (LVEF) could predict both cardiovascular mortality ( p = 0.003; HR: 4.25, 95% CI: 1.63–11.08) and total mortality ( p = 0.002; HR: 3.95, 95% CI: 1.65–9.45). Lower LVEF ( p = 0.001; HR: 0.31, 95% CI: 0.16–0.61) and small stent size ( p = 0.01; HR: 5.95, 95% CI: 1.43–24.80) could predict the composite endpoint, including target vessel revascularization and total mortality. Conclusion We showed that young age and BMS implantation could predict repeated PCI and/or CABG after stent implantation for unprotected LMCA disease. Only lower LVEF could predict both cardiovascular and total mortality. Lower LVEF and small stent size but not BMS implantation could predict composite target vessel revascularization/total mortality.

Aims To assess the diagnostic accuracy of 256-row computed tomographic angiography (CTA) in patients with suspected coronary artery disease (CAD). Non-invasive imaging of the coronary artery by CTA has increasingly been used in recent years. The accuracy of 256-row CTA has not yet been studied. We sought to assess the accuracy of 256-row CTA compared with invasive coronary angiography (ICA) in the diagnosis and assessment of CAD. Methods and results We prospectively evaluated 104 consecutive individuals who accepted CTA and then underwent ICA. The presence of stenosis ≥50% was considered obstructive. The diagnostic accuracy of CTA for detecting obstructive stenosis was compared with that of ICA. The area under the receiver-operating-characteristic curve (AUC) was used to evaluate the diagnostic accuracy of CTA relative to ICA. A total of 86 patients had obstructive CAD. The patient-based analysis of CTA for detecting stenosis ≥50% according to ICA revealed an AUC of 0.744 [95% confidence interval (CI), 0.572–0.916], with a sensitivity of 98.8%, a specificity of 50%, a positive predictive value (PPV) of 92.4%, and a negative predictive value (NPV) of 87.5%. The segment-based analysis revealed an AUC of 0.915 (95% CI, 0.847–0.982), with a sensitivity of 93.5%, a specificity of 95%, a PPV of 77.6%, and an NPV of 98.7%. The vessel-based analysis revealed an AUC of 0.887 (95% CI, 0.808–0.966), with a sensitivity of 94.3%, a specificity of 87.3%, a PPV of 82.7%, and an NPV of 95.9%. Conclusion 256-Row CTA is a highly sensitive test of CAD and has a high predictive value. 256-Row CTA may be a potential alternative to detect coronary artery stenosis and rule out CAD in suspected patients.

Background Coronary artery fistula (CAF) is an anomaly resulting in the steal phenomenon of coronary blood flow, which may cause morbidity or mortality. CAFs in Chinese patients after long-term follow-up of 15 years were retrospectively analyzed. Methods and results From September, 1992 to August, 2007, 152 CAFs were detected in 28,210 coronary angiograms from 125 patients. Clinical and angiographic data of all patients were analyzed retrospectively. Two types of CAFs were characterized: type I in 99 patients with 124 solitary coronary to cardiac chamber or great vessel fistula; type II: 26 patients with 28 coronary artery--left ventricular multiple microfistulas. Single-, double-, and triple-CAFs were detected in 79%, 20%, and 1% of patients, respectively. Coexistent coronary lesions were noted in 41% of patients. Fistula-related symptoms included stable angina in 55, myocardial infarction in 2, heart failure in 2, sudden death with ventricular fibrillation in 1, and syncope in 1. Twenty-four patients had coexistent congenital anomalies. Only 9 patients underwent coronary intervention or/and surgery for CAFs. Conclusions CAFs may cause trivial or lethal cardiac events, and may coexist with coronary lesion or congenital anomaly. Coronary to cardiac chamber or great vessel fistula and coronary-left ventricular multiple microfistulas have different morphologic and pathological phenomena.

Summary Over the past 30 years, the prevalence and incidence of heart failure (HF) have increased markedly with age, with increases of approximately fivefold from the age of 40 to 70 years. HF is predominantly a disorder of the elderly, and over 70% of HF patients are over 65 years old. The most important factor in the increasing prevalence and incidence of HF is the growing proportion of elderly with new-onset diastolic HF resulting from chronic hypertension and coronary heart disease. Other predictors of HF include diabetes, prior stroke, atrial fibrillation, renal dysfunction, reduced ankle-brachial index, increased C-reactive protein, left ventricular hypertrophy, reduced forced expiratory volume, and obesity. At least half of all elderly HF patients have preserved left ventricular systolic function, and they are classified as diastolic HF. There was a strong female predominance (67%) in diastolic HF when compared with male HF patients. The morbidity and mortality of older HF patients are the highest of any chronic cardiovascular disorder. Mortality increases markedly with age. Mortality from diastolic HF is about half of that reported for systolic HF. There are some comorbidities in older HF patients, including renal dysfunction, chronic lung disease, cognitive dysfunction, depression, postural hypotension, urine incontinence, sensory deprivation, nutritional disorders, polypharmacy and frailty, which may precipitate and exacerbate the underlying HF symptoms. Clinical diagnosis of HF may be more difficult in the elderly because of frequently inadequate history taking, less evident HF symptoms for reduced daily activity, and similar symptoms to other frequent disorders. The treatment goals in older HF patients resemble those for any chronic disorder and include relief of symptoms, improvement in functional status, exercise tolerance, quality of life, prevention of acute exacerbation, and finally, prolongation of long-term survival.

Objectives The purpose of this study was to investigate the predictor of non-pulmonary vein (PV) ectopic beats initiating paroxysmal atrial fibrillation (PAF). Background Non-PV ectopic beats can initiate PAF in some patients and play an important role in the recurrence of PAF after PV isolation. Information on the predictors of non-PV ectopic beats initiating PAF is unknown. Methods This study included 293 patients (215 men and 78 women, age 60 ± 14 years) with clinically documented drug-refractory PAF. Of the 94 patients with non-PV ectopic beats initiating PAF, 38 (40%) patients had superior vena cava (SVC) ectopic beats and 32 (34%) had left atrial posterior free wall (LAPFW) ectopic beats. Results In a univariate analysis, only female gender was related to the presence of non-PV (p = 0.016) and SVC ectopic beats (p = 0.012). Right atrial enlargement (p = 0.005) and left atrial enlargement (p Conclusions The location of non-PV ectopic beats initiating PAF can be predicted by both gender and left atrial enlargement.

The purpose of this randomised, double-blind, double-dummy, parallel-group study was to evaluate the efficacy and tolerability of telmisartan 40 mg once daily vs. enalapril 10 mg once daily in 147 Taiwanese patients with mild-to-moderate essential hypertension (diastolic blood pressure [DBP] 90-109 mmHg). After 6 weeks' treatment, telmisartan produced a significantly greater reduction from baseline in the primary endpoint of trough seated DBP compared with enalapril 10 mg (11.7 vs. 8.7 mmHg, respectively; p = 0.02). Numerically greater reductions compared with baseline in seated systolic blood pressure (SBP), standing DBP, and standing SBP were achieved with telmisartan compared with enalapril. Also, numerically greater proportions of patients achieved blood pressure control (DBP/systolic blood pressure [SBP] or = 10 mmHg and/or post-treatment DBP or = 10 mmHg and/or post-treatment SBP

Introduction: The outcome of patients with early recurrence of atrial fibrillation (AF) (within one month) after ablation procedure is controversial. Furthermore, the predictors of early and late (up to mean follow-up 30 months) recurrence of AF are not investigated in depth. Aims of the Study: The aim of the present study was to investigate the predictors of early and late recurrence of AF after catheter ablation of arrhythmogenic foci initiating AF in patients with paroxysmal AF. Methods and Results: The study included 207 patients (155 men; mean age 62 ± 13 years) who received catheter ablation of paroxysmal AF. Eighty-one (39%) patients had early recurrence of AF. Five clinical variables were related to the early recurrence of AF: (1) old age (≥65 years) (P = 0.004); (2) presence of associated cardiovascular disease (P = 0.01); (3) presence of multiple AF foci (P = 0.004); (4) presence of AF foci from left atrial free wall (P = 0.039); (5) left atrial enlargement (P = 0.038). Multivariate analysis demonstrated that presence of multiple AF foci could predict early recurrence of AF (P = 0.013; ratio = 2.24; 95% CI 1.18 to 4.25). During the follow-up period (30 ± 11 months), 70 (34%) patients had late recurrence of AF, and two clinical variables were related to the late recurrence of AF: (1) presence of early recurrence of AF (P = 0.025); (2) presence of multiple AF foci (P = 0.034). Multivariate analysis found that presence of early recurrence of AF could predict late recurrence of AF (P = 0.046; hazard ratio = 1.62; 95% CI 1.01 to 2.59). Late recurrence of AF happened in 35 (43%) of the 81 patients with early recurrence of AF, and in 35 (28%) of the 126 patients without early recurrence of AF. Conclusions: Early AF recurrence could predict late AF recurrence.

Introduction: The incidence of spontaneous transition of 2:1 AV block to 1:1 AV conduction during AV nodal reentrant tachycardia has not been well reported. Among previous studies, controversy also existed about the site of the 2:1 AV block during AV nodal reentrant tachycardia. Methods and Results: In patients with 2:1 AV block during AV nodal reentrant tachycardia, the incidence of spontaneous transition of 2:1 AV block to 1:1 AV conduction and change of electrophysiologic properties during spontaneous transition were analyzed. Among the 20 patients with 2:1 AV block during AV nodal reentrant tachycardia, a His-bundle potential was absent in blocked beats during 2:1 AV block in 8 patients, and the maximal amplitude of the His-bundle potential in the blocked beats was the same as that in the conducted beats in 4 patients and was significantly smaller than that in the conducted beats in 8 patients (0.49 ± 0.25 mV vs 0.16 ± 0.07 mV, P = 0.007). Spontaneous transition of 2:1 AV block to 1:1 AV conduction occurred in 15 (75%) of 20 patients with 2:1 AV block during AV nodal reentrant tachycardia. Spontaneous transition of 2:1 AV block to 1:1 AV conduction was associated with transient right and/or left bundle branch block. The 1:1 AV conduction with transient bundle branch block was associated with significant His-ventricular (HV) interval prolongation (66 ± 19 ms) compared with 2:1 AV block (44 ± 6 ms, P < 0.01) and 1:1 AV conduction without bundle branch block (43 ± 6 ms, P < 0.01). Conclusion: The 2:1 AV block during AV nodal reentrant tachycardia is functional; the level of block is demonstrated to be within or below the His bundle in a majority of patients with 2:1 AV block during AV nodal reentrant tachycardia, and a minority are possibly high in the junction between the AV node and His bundle. (J Cardiovasc Electrophysiol, Vol. 14, pp. 1337-1341, December 2003)

Background Cardiac sarcoidosis is a life-threatening disease with protean clinical manifestations, including congestive heart failure (CHF), conduction disturbance, ventricular arrhythmia and sudden death. Nonetheless, it is difficult to diagnose cardiac sarcoidosis in the clinical setting. Some echocardiographic findings of cardiac sarcoidosis associated with other diagnostic tools ( 201 thallium scintigraphy, 67 gallium citrate scan, serum markers and others) may be helpful upon early suspicion and diagnosis of cardiac sarcoidosis. Materials and Methods Fifty-two patients (36 female) with cardiac sarcoidosis, with a mean age of 48 ± 14 years (range, 21–70 yr), underwent a series of echocardiographic follow-up (mean, 88 ± 48 mo) examinations, and important echocardiographic parameters and findings were recorded. Results There were left ventricular (LV) regional wall motion abnormalities (RWMAs) noted in 40 (localized in 16, multiple in 24), dilatation of the LV with impaired LV contractility in 28, thinning of the basal interventricular septum (IVS) in 27, thinning of LV free wall in 18, apical aneurysm in 12, apical thrombus in two, mimicking hypertrophic cardiomyopathy (HCM) in two, pericardial effusion (PE) in two (with cardiac tamponade in one), and LV wall thinning and aneurysm formation after steroid therapy for cardiac sarcoidosis in two of 43 patients. Conclusion Thinning of the basal IVS or LV free wall is a specific echocardiographic finding of cardiac sarcoidosis. Other echocardiographic findings of cardiac sarcoidosis may mimic coronary artery disease (LV RWMA or apical aneurysm), CHF, or HCM. PE and thinning of the LV wall after steroid therapy were also noted in rare situations.

Left main coronary artery (LMCA) disease is now uniformly treated with coronary artery bypass grafting (CABG). However, some patients with LMCA disease do not receive CABG because of high operative risks. The advent of stent implantation has permitted a non-operative improvement in myocardial blood flow in many patients with single- and multi-vessel coronary artery disease. However, the outcomes of stent implantation for unprotected LMCA disease are still unclear. Stent implantation was performed for unprotected LMCA disease in 13 patients; eight patients had high operative risk and five patients had refused CABG. The primary success rate was 100% (13/13 patients). One patient (8%) developed a non-Q-wave myocardial infarction after LMCA stenting. Repeat angiography was obtained in five patients (38%) with recurrent angina, and three patients (23%) received repeated percutaneous transluminal coronary angioplasty (PTCA) for LMCA restenosis. In the follow-up period of 18±3 months, 12 patients (92%) remained in satisfactory condition with no further need for surgical intervention. One patient (8%) ultimately required CABG, and she died after CABG at 3 months after LMCA stenting. In conclusion, although CABG remains the standard treatment for LMCA disease, the present study demonstrates that stent implantation is a safe and clinically beneficial revascularization procedure for unprotected LMCA disease in patients who have high operative risk as well as those who refuse CABG.

To compare the safety and efficacy of anterior versus posterior approach for atrioventricular (AV) junction modification, 40 patients with medically refractory paroxysmal (PAF) or chronic atrial fibrillation (AF) were randomly assigned to receive AV junction modification with an anterior or posterior approach. If the ablation session had taken more than 1 hour without success, the alternative ablation approach was attempted. Among the 18 patients assigned to receive the anterior approach, 14 (78%) had a primary success. One (5%) patient had complete AV block after ablation. Three patients crossed over to the posterior approach and had a successful outcome. Fourteen (64%) of 22 patients initially treated with the posterior approach had primary success. One (4%) patient developed complete AV block. Seven patients crossed over to the anterior approach and had a successful outcome. The primary success rate (14/18 vs 14/22, P = NS), incidence of transient AV block (3/18 vs 3/22, P = NS), and complete AV block (1/18 vs 1/22, P = NS) were similar between the anterior approach and posterior approach. The major differences between the two groups showed more radiofrequency pulses (10 +/- 4 vs 6 +/- 3 pulses, P < 0.01), longer procedure duration (50 +/- 24 vs 28 +/- 18 minutes, P < 0.01), and longer fluoroscopy exposure time (28 +/- 17 vs 16 +/- 8 minutes, P < 0.01) in the patients who had primary success with the posterior approach. In conclusion, this study demonstrated that (1) the two techniques had similar efficacies; (2) if one approach was ineffective, switching to the other approach might be safe; (3) combining these two approaches resulted in overall improvement in the success rate of this procedure, and (4) the posterior approach needed more radiofrequency pulses, longer procedural time, and longer fluoroscopy exposure time.

Background —The effect of verapamil on long-term tachycardia-induced atrial electrical remodeling has not been reported. Methods and Results —Forty-eight dogs were randomly divided into verapamil and control groups. The dogs in the verapamil group received verapamil 120 mg every day, those in the control group did not receive verapamil. Atrial effective refractory period (AERP), inducibility of atrial fibrillation (AF), and duration of AF were assessed before and after complete atrioventricular junction ablation with 1-day, 1-week, or 6-week rapid atrial pacing (780 bpm). AERP shortening, AERP dispersion, AERP maladaptation, and inducibility of AF after 1-day pacing was significantly attenuated by verapamil. However, verapamil did not have any significant effect on these parameters in the dogs with 1-week or 6-week pacing. Verapamil did not have any significant effect on the conduction velocity in the dogs with 1-day, 1-week, or 6-week pacing. Before rapid atrial pacing, verapamil significantly prolonged the duration of AF. In the dogs with 1-day pacing, the duration of AF measured immediately after termination of pacing was similar between the control and verapamil groups. However, in the dogs with 1-week or 6-week pacing, the duration of AF after pacing was significantly longer in the verapamil group. Conclusions —Verapamil cannot prevent long-term (1 and 6 weeks, respectively) tachycardia-induced changes of atrial electrophysiological properties. Furthermore, verapamil increases the duration of AF in the dogs either before or after long-term rapid atrial pacing.

Background —Regional differences in recovery of tachycardia-induced changes of atrial electrophysiological properties have not been well studied. Methods and Results —In the control group (5 dogs), atrial effective refractory period (AERP) and inducibility of atrial fibrillation (AF) were assessed before and every 4 hours for 48 hours after complete atrioventricular junction (AVJ) ablation with 8-week VVI pacing. In experimental group 1 (15 dogs), AERP and inducibility of AF were assessed before and after complete AVJ ablation with 8-week rapid right atrial (RA) pacing (780 bpm) and VVI pacing. In experimental group 2 (7 dogs), AERP and inducibility of AF were assessed before and after 8-week rapid left atrial (LA) pacing and VVI pacing. AERP and inducibility and duration of AF were obtained from 7 epicardial sites. In the control group, atrial electrophysiological properties obtained immediately and during 48-hour measurements after pacing did not show any change. In the 2 experimental groups, recovery of atrial electrophysiological properties included a progressive recovery of AERP shortening, recovery of AERP maladaptation, and decrease of duration and episodes of reinduced AF. However, recovery of shortening and maladaptation of AERP and inducibility of AF was slower at the LA than at the RA and Bachmann’s bundle. Conclusions —The LA had a slower recovery of tachycardia-induced changes of atrial electrophysiological properties, and this might play a critical role in initiation of AF.

Atrial fibrillation (AF) is a common arrhythmia after coronary artery bypass surgery (CABG). The purpose of this study was to determine the role of P wave duration, amplitude and dispersion in the prediction of AF after CABG. This study included 120 patients undergoing elective CABG. Clinical characteristics, 12-lead electrocardiogram (ECG), echocardiogram and coronary angiogram were obtained in all patients. We measured P wave duration, amplitude and dispersion from 12-lead ECG in each patient. After CABG, all patients were continuously monitored for AF attacks in the intensive care unit and ordinary ward. Our results showed that age greater than 60 years was the strongest predictor of postoperative AF (p0.01), with a 3.7-fold greater likelihood of developing postoperative AF compared to ages less than 60 years. Gender was another independent predictor of postoperative AF, with men being 3.0 times more likely to develop postoperative AF compared to women (p = 0.03). The presence of prolonged P wave duration (or =100 ms in lead II) was also an independent predictor (p = 0.04), with 2.9-fold greater risk of developing postoperative AF compared to a P wave duration of less than 100 ms. The P wave dispersion was similar between patients with and without postoperative AF (29+/-15 vs. 33+/-15 mm, p = NS). In conclusion, old age, male gender and prolonged P wave duration were independent predictors of AF after CABG. However, P wave dispersion and amplitude did not provide significant information in the prediction of postoperative AF.

Cardiac troponin T is a sensitive and specific marker for the detection of minor myocardial injury. However, it has been rarely used to monitor myocardial injury after coronary stenting. The purpose of the study was to measure troponin T after apparently successful percutaneous transluminal coronary angioplasty (PTCA) with or without coronary stenting and to compare its result with serum creatine kinase and its isoform, CKMB.The incidence of cardiac troponin T elevation was compared with that of creatine kinase or CKMB in 120 consecutive patients with symptomatic ischemia undergoing visually successful PTCA with (n = 59) or without stenting (n = 61). Troponin T, creatine kinase, and CKMB were measured before, immediately after, and 18 to 24 hours after the procedures were performed.No patient had abnormal troponin T, creatine kinase, or CKMB levels before and immediately after the procedures. Moreover, no patient showed electrocardiographic evidence of myocardial infarction. Troponin T was elevated in 17 patients at 18 to 24 hours after coronary stenting and in eight patients after PTCA. Both creatine kinase and CKMB were elevated in five patients after coronary stenting and in three patients after PTCA. The frequency of abnormal troponin T levels was significantly higher than that of creatine kinase or CKMB after coronary interventions (21% vs 6.7%; p0.01), and it was significantly higher after stenting when compared with angioplasty alone (29% vs 13%; p0.05). Patients with abnormal troponin T levels were more likely to undergo repeat revascularization than those without (24% vs 6%; p0.01).Cardiac troponin T is more sensitive than creatine kinase and CKMB in detecting minor myocardial injury after coronary interventions. The incidence of troponin T release is higher in the patients undergoing stent implantation than in patients treated with angioplasty alone.

Objectives. This study compared the long-term effects of complete atrioventricular junction (AVJ) ablation with those of AVJ modification in patients with medically refractory atrial fibrillation (AF). Background. Comparisons between the long-term effects of AVJ ablation with those of AVJ modification in patients with medically refractory AF have not been systematically studied. Methods. Sixty patients with medically refractory AF were randomly assigned to receive complete AVJ ablation with permanent pacing or AVJ modification. Subjective perception of quality of life (QOL) was assessed by a semiquantitative questionnaire before and 1 and 6 months after ablation. Cardiac performance was evaluated by echocardiography and radionuclide angiography within 24 h (baseline) and at 1 and 6 months after ablation. Results. Both methods were associated with significant improvement in general QOL and a significant reduction in the frequency of major symptoms and symptoms during attacks. The frequency of hospital admission and emergency room visits and antiarrhythmic drug trials significantly decreased after ablation in both groups. However, patients after complete AVJ ablation had a significantly greater improvement in general QOL and a significantly reduced frequency of major symptoms and symptoms during attacks (including palpitation, dizziness, chest oppression, blurred vision and syncope). Left ventricular (LV) systolic function and the ability to perform activities of daily life significantly improved after ablation in patients with depressed LV function in both groups. All improvements after ablation or modification were maintained over the 6-month follow-up period. Conclusions. AVJ ablation with permanent pacing, as compared with AVJ modification, had a significantly greater ability to decrease the frequency of attacks and the extent of symptoms of AF, and the patients who received this procedure were more satisfied with their general well-being.

A 72-year-old woman who presented with transient electrocardiographic ST segment elevation and left ventricular asynergy in an acute phase of subarachnoid hemorrhage was found to have normal coronary angiogram and normal Tc-99m PYP myocardial infarct scan. These findings suggested that noninvasive Tc-99m PYP myocardial infarct scan could substitute coronary angiogram for differentiating wall motion and electrocardiographic abnormalities secondary to subarachnoid hemorrhage from those caused by coronary artery disease in patients with subarachnoid hemorrhage.

BACKGROUND Currently, the door-to-balloon (D2B) times observed in clinical practice in Taiwan are different from those recommended by evidence-based guidelines. D2B Alliance, a countrywide initiative for quality supported by the Taiwan Joint Commission on Hospital Accreditation, sought to achieve the goal of administering treatment to 75% of patients with ST-elevation myocardial infarction (STEMI) within 90min of hospital presentation. METHODS AND RESULTS The current study was designed to be prospective, national, and multicenter. We conducted a longitudinal study of the D2B times recorded in 15 primary percutaneous coronary intervention centers and examined the changes caused by implementing the D2B Alliance strategies. A total of 1,726 patients were enrolled in the D2B Alliance and implementation of the D2B Alliance strategies resulted in a significant decrease in the average D2B times (128.8 ± 42.9 min vs. 83.2 ± 16.2 min; P

To compare transthoracic and transesophageal echocardiography in the diagnosis of intracardiac tumors, 17 patients (8 men and 9 women, aged 19 years to 67 years) whose intracardiac tumors were detected by echocardiography were studied in a 4-year period. Of these, 14 patients underwent cardiac surgery and 13 were proved to have tumors. There were 4 false-positive and 2 false-negative diagnoses by transthoracic echocardiography, but only one false-positive and no false-negative diagnosis by transesophageal echocardiography. The stalk of a myxoma was detected clearly in 5 of 11 patients by transthoracic echocardiography, whereas in 10 of 11 it was detected by transesophageal echocardiography. The detailed morphologic characteristics of the tumor, such as contour of the tumor, and the presence of cysts and calcification in the tumor, were seen more clearly with transesophageal echocardiography than with transthoracic echocardiography.

BACKGROUND Gastrointestinal bleeding is a hemorrhagic complication after primary percutaneous coronary intervention in patients with ST-segment elevation myocardial infarction (STEMI). OBJECTIVES To determine predictors of gastrointestinal bleeding and the impact of gastrointestinal bleeding on outcomes in STEMI patients undergoing primary percutaneous coronary intervention. METHODS AND RESULTS Gastrointestinal bleeding occurred in 18 (3.5%) of 519 consecutive patients with STEMI undergoing primary percutaneous coronary intervention. Univariate predictors of gastrointestinal bleeding were previous gastrointestinal bleeding (33% vs 4%, P < .001), impaired renal function (89% vs 37%, P

Systemic arterial embolization imparts a significant risk of serious complications throughout the lives of patients with rheumatic heart disease. Left atrial (LA) thrombi have been thought to be the major source of emboli. A transesophageal echocardiography (TEE) study of 260 consecutive patients with rheumatic mitral valve disease was performed during a period of 24 months, with particular reference to understanding the association between LA thrombi and embolic complications. Of these patients, 155 had predominant mitral stenosis, 24 had significant mitral regurgitation, and the remaining 81 with xenograft mitral valve replacement developed valvular dysfunction (25 resulted in predominant mitral stenosis and 56 in significant mitral regurgitation). LA thrombi were detected in 38 patients (group A) and absent in 222 (group B). Group A patients had a higher frequency of recent (less than or equal to 1 week before TEE study) and remote (greater than 1 week before) embolization than did group B patients (recent: 26.3 vs 5.4% [p less than 0.001]; remote: 18.4 vs 5.0% [p less than 0.01]). The frequency of atrial fibrillation was also greater in group A patients (100 vs 74.3%; p less than 0.001). The exclusion of patients with significant mitral regurgitation and sinus rhythm had no effect on the association between LA thrombi and evidence of previous embolization. It is concluded that TEE is a convenient diagnostic modality that can be used to identify a subset of patients with rheumatic mitral valve disease at high risk for systemic embolization. Consequently, preventive anticoagulation for possible embolic complications should be more vigorously adhered to in patients with rheumatic mitral valve disease and LA thrombi.

Background/PurposeKnowledge concerning subacute stent thrombosis (SST) following primary stenting for ST-elevation myocardial infarction (STEMI) is not widely available. We studied the incidence, predictors, and clinical outcomes of SST following STEMI.MethodsWe analyzed data from 455 consecutive patients who underwent primary stenting for STEMI. Baseline clinical characteristics, coronary angiographic features, medication and outcome were compared in patients with and without SST.ResultsSST occurred in 17 patients, and the incidence was 3.7%. Univariate predictors of SST were being a current smoker (53.0% vs. 82.4%, p = 0.01), Killip class ≥ II (38.4% vs. 58.8%, p = 0.05), no coronary re-flow after stenting (6.2% vs. 17.6%, p = 0.05) and lack of coprescription with a statin (39.5% vs. 5.9%, p

Left circumflex (LC)-related acute myocardial infarction (AMI) presenting without ST-T changes has been underdiagnosed in the emergency department. There is little information on its clinical features and significance.The aims of the study were to investigate the clinical characteristics and outcomes of LC-related AMI without ST-T changes.Ninety-six patients were admitted for LC-related AMI. Comparisons between those with and without ST-T changes were analyzed.Twenty-two patients (23%) did not have ST-T changes, whereas 74 patients (77%) had them. Patients without ST-T changes had younger age (55.6 + or - 16.8 vs 62.6 + or - 12.0 years, P = .03), fewer presented as Killip III/IV (4.5% vs 27.4%, P = .02) and with lower creatine kinase (1647.3 + or - 1602.2 vs 2778.2 + or - 2343.3 IU/L, P = .037) and creatine kinase-MB (136.8 + or - 130.3 vs 247.7 + or - 200.0 IU/L, P = .017), and more were with concurrent culprit lesion in the middle or distal LC and right- or balanced-dominant coronary circulation (86.4% vs 44.6%, P.001). During follow-up, the need for repeat percutaneous coronary intervention (48.6% vs 45.5%, P = .40) and recurrent infarction (13.5% vs 13.6%, P = .62) were similar between the 2 groups. The 30-day mortality (0% vs 5.4%, P = .35) and overall mortality rate (4.5% vs 12.2%, P = .28) between them were not different statistically.The relatively lower prevalence of LC-related AMI without ST-T changes in the study might be underestimated. These patients have smaller infarct size than patients with ST-T changes without differences in the short- and long-term outcomes between them.

The purpose of this study was to investigate the predictor of long-term outcomes in patients after stent implantation for unprotected left main coronary artery (LMCA) disease. Coronary stenting has recently been advocated as an alternative procedure for LMCA disease. Information on the predictors of long-term outcomes in patients after stent implantation for unprotected LMCA disease is not clear. Seventy six patients (51 men and 25 women, age 68 +/- 10 years) with medically refractory angina received coronary stenting for unprotected LMCA disease. During a follow-up period of 40 +/- 26 months, 7 patients (9%) died because of cardiovascular disease in 5 (7%) and noncardiovascular disease in 2 (3%). In the other 69 patients, 19 patients (25%) needed repeated percutaneous coronary intervention (PCI) and/or coronary artery bypass grafting (CABG). In a univariate analysis, only female sex was related to the repeated PCI and/or CABG (P = 0.04). A history of cerebral vascular attack (CVA) (P = 0.005), anemia (P = 0.03) and lower left ventricular ejection fraction (LVEF) (P = 0.008) were related to the cardiovascular mortality. A history of myocardial infarction (P = 0.03), a history of CVA (P = 0.02), anemia (P = 0.02), and lower LVEF (P = 0.002) were related to the total mortality. In a multivariate analysis, female sex (P = 0.007; odds ratio 5.29, 95% confidence interval [CI] 1.57-17.80) and young age (P = 0.025; odds ratio 3.92, 95% CI 1.19-12.98) could predict the repeated PCI and/or CABG. Only a history of CVA could predict the cardiovascular mortality (P = 0.027; odds ratio 34.18, 95% CI 1.49-783) and only lower LVEF could predict the total mortality (P = 0.027; odds ratio 13.26, 95% CI 1.34-131). Female sex and young age could predict the repeated PCI and/or CABG in patients after stent implantation for unprotected LMCA disease. Furthermore, a history of CVA could predict the cardiovascular mortality and lower LVEF could predict the total mortality.

Background: Junctional rhythm (JR) is commonly observed during radiofrequency (RF) ablation of the slow pathway for atrioventricular (AV) nodal reentrant tachycardia. However, the atrial activation pattern and conduction time from the His-bundle region to the atria recorded during JR in different types of AV nodal reentrant tachycardia have not been fully defined. Methods: Forty-five patients who underwent RF ablation of the slow pathway for AV nodal reentrant tachycardia were included; 27 patients with slow-fast, 11 patients with slow-intermediate, and 7 patients with fast-slow AV nodal reentrant tachycardia. The atrial activation pattern and HA interval (from the His-bundle potential to the atrial recording of the high right atrial catheter) during AV nodal reentrant tachycardia (HA S V T ) and JR (HA J R ) were analyzed. Results: In all patients with slow-fast AV nodal reentrant tachycardia, the atrial activation sequence recorded during JR was similar to that of the retrograde fast pathway, and transient retrograde conduction block during JR was found in 1 (4%) patient. The HA J R was significantly shorter than the HA S V T (57 ′ 24 vs 68 ′ 21 ms, P < 0.01). In patients with slow-intermediate AV nodal reentrant tachycardia, the atrial activation sequence of the JR was similar to that of the retrograde fast pathway in 5 (45%), and to that of the retrograde intermediate pathway in 6 (55%) patients. Transient retrograde conduction block during JR was noted in 1 (9%) patient. The HAIR was also significantly shorter than the HA S V T (145 ′ 27 vs 168 ′ 29 ms, P= 0.014). In patients with fast-slow AV nodal reentrant tachycardia, retrograde conduction with block during JR was noted in 7(100%)patients. The incidence of retrograde conduction block during JR was higher in fast-slow AV nodal reentrant tachycardia than slow-fast (7/7 vs 1/11, P < 0.01) and slow-intermediate AV nodal reentrant tachycardia (7/7 vs ½7, P < 0.01). Conclusions: In patients with slow-fast and slow-intermediate AV nodal reentrant tachycardia, the JR during ablation of the slow pathway conducted to the atria through the fast or intermediate pathway. In patients with fast-slow AV nodal reentrant tachycardia, there was no retrograde conduction during JR. These findings suggested there were different characteristics of the JR during slow-pathway ablation of different types of AV nodal reentrant tachycardia.

ObjectivesWe sought to evaluate the efficacy of the antioxidant acetylcysteine in limiting the nephrotoxicity after coronary procedures.BackgroundThe increasingly frequent use of contrast-enhanced imaging for diagnosis or intervention in patients with coronary artery disease has generated concern about the avoidance of contrast-induced nephrotoxicity (CIN). Reactive oxygen species have been shown to cause CIN.MethodsWe prospectively studied 121 patients with chronic renal insufficiency (mean [±SD] serum creatinine concentration 2.8 ± 0.8 mg/dl) who underwent a coronary procedure. Patients were randomly assigned to receive either acetylcysteine (400 mg orally twice daily) and 0.45% saline intravenously, before and after injection of the contrast agent, or placebo and 0.45% saline. Serum creatinine and blood urea nitrogen were measured before, 48 h and 7 days after the coronary procedure.ResultsSeventeen (14%) of the 121 patients had an increase in their serum creatinine concentration of at least 0.5 mg/dl at 48 h after administration of the contrast agent: 2 (3.3%) of the 60 patients in the acetylcysteine group and 15 (24.6%) of the 61 patients in the control group (p < 0.001). In the acetylcysteine group, the mean serum creatinine concentration decreased significantly from 2.8 ± 0.8 to 2.5 ± 1.0 mg/dl (p < 0.01) at 48 h after injection of the contrast medium, whereas in the control group, the mean serum creatinine concentration increased significantly from 2.8 ± 0.8 to 3.1 ± 1.0 mg/dl (p < 0.01).ConclusionsProphylactic oral administration of the antioxidant acetylcysteine, along with hydration, reduces the acute renal damage induced by a contrast agent in patients with chronic renal insufficiency undergoing a coronary procedure.

Atrial fibrillation occurs in 10% to 40% of patients who undergo coronary artery bypass grafting. This prospective study assesses the safety and efficacy of low-dose intravenous amiodarone in the prevention of atrial fibrillation after coronary artery bypass grafting.One hundred forty patients were randomly divided into two groups: an amiodarone group (n = 74) receiving intravenous amiadarone in a loading dose of 150 mg and maintenance dose of 0.4 mg x kg(-1) x h(-1) for 3 days before and 5 days after operation and a control group (n = 76) receiving matching infusions of 5% glucose solution.Atrial fibrillation occurred in 9 (12%) of the amiodarone group patients and in 26 (34%) of the control group patients during hospitalization (p0.01). The maximum ventricular rate during atrial fibrillation was significantly slower in the amiodarone group (107 +/- 21) than in the control group (138 +/- 24 beats per minute, p0.01). The duration of atrial fibrillation in the amiodarone group (1.1 +/- 1.2 hours) was significantly shorter than that in the control group (3.2 +/- 1.3 hours, p = 0.01). The two groups had no significant differences in incidence of major morbidity (8 of 74 versus 8 of 76 in amiodarone and control groups, respectively) or mortality (4 of 74 versus 5 of 76). However, the control group had significantly longer intensive care unit stays (132 +/- 24 versus 111 +/- 19 hours, p0.01).Perioperative low-dose intravenous amiodarone significantly reduces the incidence, ventricular rate, and duration of atrial fibrillation after coronary artery bypass grafting. Furthermore, low-dose intravenous amiodarone is well tolerated and does not increase the risk of intraoperative or postoperative complications.

Background: Various clinical manifestations of cardiovascular diseases have a pattern of circadian variation. In this study, we investigated whether the onset and duration of paroxysmal supraventricular tachycardia (PSVT) has a circadian variation. Methods and results: In our analysis, we included 105 patients with 498 PSVT episodes. In this study, the onset of PSVT did not have a uniform distribution throughout the 24-h period. There were nearly equal peaks in the time periods from 8:00 to 9:00 AM, 12:00 to 1:00 PM, and 5:00 to 6:00 PM, with a trough at night. The duration of PSVT also did not show a uniform distribution throughout the 24-h period; it increased significantly during the daytime, with a peak between 1:00 and 2:00 PM, another peak between 6:00 and 7:00 PM, and a significant reduction at night. Conclusions: The onset and duration of PSVT showed a circadian variation. However, the time-oriented antiarrhythmic therapy for preventing PSVT needs further study. (CHEST 1999; 115:674 ‐ 678)

Detailed electrophysiologic study of AV nodal reentrant tachycardia (AVNRT) with 2:1 AV block has been limited.Six hundred nine consecutive patients with AVNRT underwent electrophysiologic study and radiofrequency catheter ablation of the slow pathway. Twenty-six patients with 2:1 AV block during AVNRT were designated as group I, and those without this particular finding were designated as group II. The major findings of the present study were: (1) group I patients had better anterograde and retrograde AV nodal function, shorter tachycardia cycle length (during tachycardia with 1:1 conduction) (307 +/- 30 vs 360 +/- 58 msec, P0.001), and higher incidence of transient bundle branch block during tachycardia (18/26 vs 43/609, P0.001) than group II patients; (2) 21 (80.8%) group I patients had alternans of AA intervals during AVNRT with 2:1 AV block. Longer AH intervals (264 +/- 26 vs 253 +/- 27 msec, P = 0.031) were associated with the blocked beats. However, similar HA intervals (51 +/- 12 vs 50 +/- 12 msec, P = 0.363) and similar HV intervals (53 +/- 11 vs 52 +/- 12, P = 0.834) were found in the blocked and conducted beats; (3) ventricular extrastimulation before or during the His-bundle refractory period bundle could convert 2:1 AV block to 1:1 AV conduction.Fast reentrant circuit, rather than underlying impaired conduction of the distal AV node or infranodal area, might account for second-degree AV block during AVNRT. Slow pathway ablation is safe and effective in patients who have AVNRT with 2:1 AV block.

The main goal of this study is to evaluate the safety and efficacy of propafenone versus sotalol as an initial choice of treatment in patients with symptomatic paroxysmal atrial fibrillation (AF), according to a double-blind randomized system. In the oral propafenone group (n = 41), 2 patients (5%) discontinued therapy because of gastrointestinal discomfort in 1 and dizziness in the other. Thirty-one (79%) of the 39 patients who continued the treatment had effective response to oral propafenone (>75% reduction of symptomatic arrhythmic attacks) on a mean dose of 663 ± 99 mg/day with a decrease in attack frequency from 10 ± 3 to 2 ± 1 times per week. In the oral sotalol group (n = 38), 4 patients (11%) discontinued treatment because of dizziness in 2 and symptomatic bradycardia in 2. Twenty-six of the 34 patients (76%) who continued the treatment had effective response to oral sotalol on a mean dose of 200 ± 57 mg/day with a decrease in attack frequency from 11 ± 3 to 2 ± 1 times per week. Comparisons of the results between propafenone and sotalol groups showed a similar incidence of intolerable (2 of 41 vs 4 of 38, p = 0.42) and tolerable side effects (10 of 39 vs 8 of 34, p = 1.0). The attack frequency at baseline (11 ± 3 vs 10 ± 4 times per week, p = 0.23) and after treatment (3 ± 1 vs 3 ± 2 times per week, p = 0.85) did not differ significantly between the 2 groups. The incidence of effective response to drugs was also similar (31 of 39 vs 26 of 34, p = 0.78). Furthermore, the decrease of symptom scores (−32 ± 8% vs −29 ± 7%, p = 0.18) and percentage decrease of ventricular rate (−15 ± 4% vs −18 ± 4%, p = 0.10) during AF were also similar between the 2 groups. In conclusion, oral propafenone and sotalol are equally effective and safe in preventing attacks and alleviating symptoms of paroxysmal AF. A double-blind randomized study protocol was designed to evaluate the safety and efficacy of propafenone versus sotalol as an initial choice of treatment in 79 patients with frequent attacks of symptomatic paroxysmal atrial fibrillation. The study result demonstrated that oral propafenone and sotalol were equally effective and safe in preventing attacks and alleviating symptoms of paroxysmal atrial fibrillation.

Among 1,281 patients with symptomatic supraventricular tachycardia, 34 patients (2.7%) with presumed diagnosis of atrioventricular node reentrant tachycardia and orthodromic atrioventricular reciprocating tachycardia did not have inducible tachycardia in the electrophysiologic laboratory. Application of radiofrequency energy to the presumed arrhythmogenic sites could achieve a high success rate, with a low recurrence rate in these patients.

Recent genotype-phenotype correlation studies in familial hypertrophic cardiomyopathy (FHC) have revealed that some mutations in the beta- myosin heavy chain (BMHC) gene may be associated with a high incidence of sudden death and a poor prognosis. Coexistence of sudden death and end-stage heart failure in several families with FHC has recently being reported; however, the genetic basis of such families has not been clearly demonstrated. A three-generation Chinese familial hypertrophic cardiomyopathy (FHC) family (family HLI) with two cases of end-stage heart failure and three cases of sudden death was analyzed. The average age of death in the affected members in this family was 34 years old. Genetic linkage analysis using polymorphisms in the (alpha- and beta-myosin heavy chain genes revealed that FHC in this family is significantly linked to the BMHC gene without recombinations. Single-strand conformation polymorphism analysis of exons 8, 9 and 13 to 23 in the BMHC gene showed a polymorphic band on exon 14 that is in complete linkage with the disease status in this family. DNA sequencing analysis in the affected members revealed an 453Arg--Cys mutation in the BMHC gene. To our knowledge this is the first reported mutation of FHC in Chinese. Our data suggest that the 453Arg--Cys mutation is associated with a malignant clinical course in FHC due not only to sudden death but also to end-stage heart failure.

The association between left atrial spontaneous echo contrast (SEC) and a history of systemic arterial embolization was evaluated in 359 consecutive patients with rheumatic mitral valve disease during a 3-year period. All patients underwent transesophageal echocardiographic (TEE) and cardiac catheterization studies. Of these, 207 patients had predominant mitral stenosis, 55 had significant mitral regurgitation, and the remaining 97 with xenograft mitral valve replacement developed valvular dysfunction (32 resulted in predominant mitral stenosis and 65 in significant mitral regurgitation). Left atrial SEC was detected in 108 patients (group A) and was absent in 251 (group B). Group A patients showed a higher frequency of left atrial thrombi or history of previous embolization than those in group B (59.3% vs 7.2%; p0.001). Group A patients also had a higher frequency of recent (or = 1 week before TEE study) and remote (1 week before TEE study) embolization than did group B patients (recent: 19.4% vs 2.8% [p0.001]; remote: 13.0% vs 4.0% [p0.001]). Multivariate analysis showed that left atrial SEC (p = 0.01) was the only independent predictor of systemic arterial embolization. It is concluded that patients with left atrial SEC had a significantly higher risk for thromboembolism, and TEE is a useful modality to identify this subset of patients with rheumatic mitral valve disease.

Objectives. The purpose of the study was to investigate the hypothesis that nodal approaches of both anterior and posterior atrial input sites of the atrioventricular (AV) node contribute to part of the circuit of AV node reentrant tachycardia. Thus, tachycardia might be elicited by a premature atrial impulse that arrived at the AV node through one input site while blocked at another. Background. Atrioventricular node reentrant tachycardia is the most common supraventricular tachycardia in humans, yet the exact pathway of the reentrant circuit is unknown. Methods. In eight dogs, an operation that blocked atrial impulses from the anterior input site to the AV node was performed through a right thoracotomy with the inflow occlusion method. The right atrial free wall and the anterior atrial septum between the sinoatrial node and the AV node were completely divided, whereas the tissues within the triangle of Koch remained intact. Thus, atrial impulses were blocked from the anterior input site in the right atrium and the atrial septum and were conducted only through the left atrial free wall to the posterior atrial septum into the AV node. Results. In a baseline electrophysiologic study before operation, dual AV conduction pathways were demonstrated in seven of eight dogs, but none of the seven had inducible AV node reentrant tachycardia. A repeat study 1 week postoperatively revealed that 1) both PR and AH intervals were prolonged during sinus rhythm (p < 0.01); 2) anterograde and retrograde conduction of the AV node showed no significant changes; and 3) AV node reentrant tachycardia was induced in four dogs (50%), of which three had sustained tachycardia. Conclusions. These results are compatible with the hypothesis that both nodal approaches of atrial input sites of the AV node contribute to part of the circuit of AV node reentrant tachycardia. They also confirm Moe's hypothesis of the existence of a brake system that prevents sustained AV node reentry. Our data suggest that the brake system is located in the anterior atrial septum.

Spontaneous echo contrast is uncommon in pericardial effusion. We report the case of a patient with massive malignant pericardial effusion causing cardiac tamponade in which the intense spontaneous echo contrast was found in the effusion by echocardiography. It was suggested that both the heavy blood content and a large amount of pericardial effusion were needed to create the phenomenon of spontaneous echo contrast in the pericardial cavity.

To ascertain the incidence and significance of bacteremia associated with transesophageal echocardiography (TEE), 132 consecutive patients (aged 17 to 73 years) free of apparent infection who were undergoing 135 transesophageal echocardiographic procedures from October 1990 to August 1991, were prospectively studied. For each procedure, two sets of blood cultures were obtained for culture 30 to 60 minutes before TEE, immediately after, and 180 to 240 minutes after the procedure. For each blood culture, 10 ml of venous blood was evenly inoculated into aerobic and anaerobic culture bottles and inoculated for 7 days using a radiometric system. A throat swab was obtained immediately before each procedure. Three of 270 preprocedure blood cultures were positive for Bacillus cereus, Staphylococcus simulans , and Peptostreptococcus species, respectively. No blood culture was positive in the immediate postprocedure period. Two of 270 late blood samples grew Staphylococcus epidermidis in the same patient. Nevertheless, the microorganisms isolated from blood cultures were different from those isolated from the throat swab. No patients had fever or evidence of infective endocarditis after TEE during the follow-up period. It is concluded that the incidence of TEE-related bacteremia is extremely low, and a general recommendation for antibiotic prophylaxis during TEE is not warranted.

Two patients had local dermal hypersensitivity at the site of dobutamine hydrochloride (Dobutrex solution) injection. Such local dermal lesions characterized by erythema, pruritus, and phlebitis with or without bullae formation have not been reported previously (to our knowledge). Hypersensitivity reaction to sulfites as a possible mechanism of the dermal lesions was substantiated further by skin tests and peripheral eosinophilia. Oral antihistamine therapy can minimize such a minor but bothersome problem.