Functional assessment of the fontan operation: Combined M-mode, two-dimensional and doppler echocardiographic studies

Combined M-mode, two-dimensional and Doppler echocardiographie studies were used to assess the postoperative status of 33 patients who had undergone the modified Fontan procedure. Twenty-four patients had surgical repair with use of a simple direct right atrium to pulmonary artery anastomosis. The remaining patients had repair with use of a prosthesis or associated Glenn shunt. Twenty-seven patients were studied early in the postoperative period (2 months or less) and the remaining patients were studied up to 6 years postoperatively. A total of 36 examinations were performed. Of the 33 patients, 13 had tricuspid atresia, 12 had double inlet left ventricle with hypoplastic right ventricular outlet chamber and 8 had complex lesions with atrioventricular canal, double outlet right ventricle or a hypoplastic ventricle.Postoperative assessment by M-mode and two-dimensional echocardiography demonstrated normal or mildly reduced ventricular function (ejection fraction > 40%) in 22 patients. In 24 patients, a “normal” (low pattern was observed in the pulmonary artery by pulsed Doppler echocardiography, with predominant diastolic flow and accentuation by atrial systole somewhat similar to the venous flow pattern observed in the superior vena cava. “Abnormal” flow patterns (disorganized systolic flow, absence of atrial waves and little or no increase with inspiration) were observed in nine patients with reduced ventricular function or residual shunt. Continuous wave Doppler study also demonstrated mild dynamic subaortic obstruction in two patients. Combined pulsed and continuous wave studies showed atrioventricular valve insufficiency in 10 patients. Follow-up studies revealed a satisfactory clinical course in most patients. Three patients died approximately 4 to 8 months after their Fontan operation

Atrial Fibrillation and Stroke in Elderly Patients

The increasing prevalence of stroke, with an estimated annual cost of $71.5 billion, has made it a major health problem that increases disability and death, particularly in patients with atrial fibrillation. Although advanced age and atrial fibrillation are recognized as strong risk factors for stroke, the basis for this susceptibility are not well defined. Aging or associated diseases are accompanied by changes in rheostatic, humoral, metabolic and hemodynamic factors that may contribute more to stroke predisposition than rhythm abnormality alone. Several thromboembolism-predisposing clinical characteristics and serum biomarkers with prognostic significance have been identified in patients with atrial fibrillation. Although anticoagulation decreases the risk of thromboembolism, management in the elderly remains complex due to major concerns about bleeding. New anticoagulants and nonpharmacologic strategies are helpful to reduce the risk of bleeding, particularly in older-elderly patients. Herein, we review the pathogenesis and management of select issues of thromboembolism in the elderly with atrial fibrillation

Outcome of Patients With Hypertrophic Cardiomyopathy and a Normal Electrocardiogram

ObjectivesThis study sought to clarify the frequency, clinical phenotype, and prognosis of those patients with hypertrophic cardiomyopathy (HCM) who present with a normal electrocardiogram (ECG).BackgroundHypertrophic cardiomyopathy is the most common cause of sudden death in young people. Screening advocates have recommended a 12-lead ECG for the early detection of HCM in athletes, yet the clinical outcomes of those presenting with a normal ECG remains to be fully delineated.MethodsBaseline characteristic and echocardiographic data were collected on all patients with HCM who initially presented to our institution with a diagnostic echocardiogram but a normal ECG. Follow-up was obtained and compared with the prognosis of HCM patients who presented with abnormal ECGs.ResultsWe compared 135 HCM patients with a normal ECG with 2,350 HCM patients with an abnormal ECG. The latter group was more likely to have worse symptoms, have higher gradients, and a greater degree of septal wall thickness than the patients with a normal ECG. Severe obstructive symptoms requiring surgical myectomy and implantation of an implantable cardioverter-defibrillator were more common in patients with abnormal ECGs. Cardiac survival was significantly better in the group with a normal ECG at presentation—none of these patients had a cardiac death at follow-up.ConclusionsAlmost 6% of patients presenting with demonstrable echocardiographic evidence of HCM had a normal ECG at the time of diagnosis. This subset of patients with normal ECG-HCM appears to exhibit a less severe phenotype with better cardiovascular outcomes

906-61 Acoustic Quantification in the Infarcted Ventricle: Comparison with Electron Beam Computed Tomography

Assessment of LV size and function by acoustic quantification (AQ) correlates well with other techniques in patients with normally contracting ventricles. This prospective study examined the correlation between AQ and electron beam computed tomography (EBCT) volume measurements in patients with first anterior Q-wave MI and abnormally contracting ventricles. End-diastolic (EDV) and end-systolic (ESV) volumes by AQ were determined from standard four-chamber (4ch) and two-chamber (2ch) apical windows. The AQ tracings were transformed to volumetric measurements using the area-length (AL) and the modified Simpson's (mod.S) methods. EDV and ESV by EBCT were obtained conventionally by summation of manually traced LV areas on each short axis tomograms using Simpson's rule. Thirteen patients were imaged by both EBCT and echocardiography within 24 hours. EBCT-EDV ranged from 129–234ml (mean 173±34 ml and ESV from 58–109ml (mean 82±19 ml). The EDV and ESV by AQ, their correlation to EBCT and the accompanying pvalues are shown below:EDV-2chEDV-4chESV-2chESV-4chVol (ml)88±3097±3043±2050±22ALr0.760.560.580.34p0.0060.0490.0610.258Vol (ml)80±3390±3140±2145±20mod.Sr0.760.700.720.58p0.0060.0080.0120.037Conclusions[1] AQ underestimates absolute EDV and ESV measured by EBCT. [2] AQ-EDV correlates well with EBCT, particularly using the mod.S method. [3] AQ-ESV correlation to EBCT drops due to the asymmetric contraction pattern of infarcted ventricles. [4] The AL method's accuracy is particularly susceptible to asymmetric contraction in distorted ventricles. [5] Correction factors can be applied to account for the offset of EDV and ESV measurements by AQ

763-6 Septal Myectomy for Hypertrophic Cardiomyopathy: Echocardiographic Predictors of Postoperative Outcome

Although septal myectomy (SM) reduces the left ventricular outflow tract (LVOT) pressure gradient and relieves symptoms in the majority of patients with severe hypertrophic cardiomyopathy (HCM). there remains a subset of patients who will continue to have residual limiting symptoms.In order to determine whether echo/Doppler (ECHO) can predict outcome after surgical treatment of HCM, we analyzed the clinical and ECHO characteristics of 47 consecutive HCM patients aged 20 to 70 years (mean 47±15 years, M:F=1:1) undergoing isolated SM from 1986 to 1992 for NYHA class 3 or 4 symptoms. Preoperative symptoms included dyspnea (100%), angina (64%), near syncope (62%), and syncope (23%).At postoperative follow-up (12±4 months). there was marked overall improvement; 94% were NYHA class 1 or 2. Persistent symptoms were dyspnea (55%), angina (15%), and near syncope (15%). By multivariate analysis of all clinical and ECHO parameters, only the preoperative ECHO variable of hypertrophy pattern (diffuse hypertrophy≥15mm versus septal localization±anterolateral extension) emerged as an independent predictor of residual dyspnea postoperatively (p=0.05). Variables not predictive included peak rest and provoked LVOT gradient, ejection time, mitral regurgitation severity, mitral flow velocity curves, left atrial volume, and left ventricular mass index.ConclusionsWith the successful relief of LVOT obstruction by SM, most HCM patients experience significant improvement in symptoms of angina. near syncope, and syncope. The morphological characteristic of diffuse (concentric) left ventricular hypertrophy is a superior predictor of residual postoperative dyspnea as compared to Doppler parameters. This diffuse hypertrophy may be indicative of severe diastolic filling abnormalities which are unchanged by SM

Epicardial vasomotor responses to acetylcholine are not predicted by coronary atherosclerosis as assessed by intracoronary ultrasound

Objectives.The purpose of this study was to use intravascular ultrasound to determine the morphologic appearance of the coronary arteries, relating the absence, presence and extent of atherosclerosis to the response of the coronary arteries to acetylcholine infusion.Background.Endothelial function plays a major role in the pathophysiology of myocardial ischemia and angina pectoris. The response of the coronary arteries to selective infusion of acetylcholine has been used to examine endothelial function, with vasoconstriction occurring in the absence of intact endothelial function. Vasoconstriction to acetylcholine infusion in humans without overt coronary artery disease has been attributed to early atherosclerosis not detected by coronary angiography.Methods.Twenty-nine patients without overt coronary artery disease underwent selective coronary angiography and selective intracoronary infusion of increasing concentrations of acetylcholine (10−6, 10−5and 10−4mol/liter), followed by intravascular ultrasound imaging.Results.The response of the coronary arteries to acetylcholine infusion was not dependent on the absence or presence of atherosclerotic plaque, as detected by intravascular ultrasound. The percent change in epicardial coronary artery diameter during acetylcholine infusion versus baseline was −14 ± 28% (mean ± SD) in the seven patients with no visible atherosclerosis on intravascular ultrasound versus −9 ± 20% in the 22 patients with visible atherosclerosis on intravascular ultrasound (p = NS, confidence interval −14% to 25%). There was a greater vasoconstrictive response to acetylcholine infusion in patients with risk factors for coronary artery disease than in those without risk factors (p = 0.003).Conclusions.The vasoreactive response to acetylcholine is not necessarily dependent on ultrasound detection of the presence or absence of atherosclerosis

Intraoperative evaluation of mitral valve regurgitation and repair by transesophageal echocardiography: Incidence and significance of systolic anterior motion

AbstractObjectives. This study was designed to delineate the utility and results of intraoperative transesophageal echocardiography in the evaluation of patients undergoing mural valve repair for mitral regurgitation.Background. Mitral valve reconstruction offers many advantages over prosthetic valve replacement. Intraoperative assessment of valve competence after repair is vital to the effectiveness of this procedure.Methods. Intraoperative transesophageal echocardiography was performed in 143 patients undergoing mitral valve repair over a period of 23 months, Before and after repair, the functional morphology of the mitral apparatus was defined by twodimensional echocardiography; Doppler color flow imaging was used to clarify the mechanism of mitral regurgitation and to semiquantitate its severity.Results. There was significant improvement in the mean mitral regurgitation grade by composite intraoperative transesophageal echocardiography after valve repair (3.6 ± 0.8 to 0.7 ± 0.7; p < 0.00001). Excellent results from initial repair with grade ≤ 1 residual mitral regurgitation were observed in 88.1% of patients. Significant residual mitral regurgitation (grade ≥ 3) was identified in 11 patients (7.7%); 5 underwent prosthetic valve replacement, 5 had revision of the initial repair and 1 patient had observation only. Of the 100 patients with a myxomatous mitral valve, the risk of grade ≥ 3 mitral regurgitation after initial repair was 1.7% in patients with isolated posterior leaflet disease compared with 22.5% in patients with anterior or bileaflet disease.Severe systolic anterior motion of the mitral apparatus causing grade 2 to 4 mitral regurgitation was present in 13 patients (9.1%) after cardiopulmonary bypass. In 8 patients (5.6%), systolic anterior motion resolved immediately with correction of hyperdynamic hemodynamic status, resulting in grade ≤ 1 residual mitral regurgitation without further operative intervention.Transthoracic echocardiography before hospital discharge demonstrated grade ≤ 1 residual mitral regurgitation in 86.4% of 132 patients studied. A significant discrepancy (> 1 grade) in residual mitral regurgitation by predischarge transthoracic versus intraoperative transesophageal echocardiography was noted in 17 patients (12.9%).Conclusions. Transesophageal echocardiography is a valuable adjunct in the intraoperative assessment of mitral valve repair