Clinical and echocardiographic characteristics of papillary fibroelastomas: a retrospective and prospective study in 162 patients.

BACKGROUND: Cardiac papillary fibroelastoma (CPF) is a primary cardiac neoplasm that is increasingly detected by echocardiography. The clinical manifestations of this entity are not well described. METHODS AND RESULTS: In a 16-year period, we identified patients with CPF from our pathology and echocardiography databases. A total of 162 patients had pathologically confirmed CPF. Echocardiography was performed in 141 patients with 158 CPFs, and 48 patients had CPFs that were not visible by echocardiography (<0.2 cm), leaving an echocardiographic subgroup of 93 patients with 110 CPFs. An additional 45 patients with a presumed diagnosis of CPF were identified. The mean age of the patients was 60+/-16 years of age, and 46.1% were male. Echocardiographically, the mean size of the CPFs was 9+/-4.6 mm; 82.7% occurred on valves (aortic more than mitral), 43.6% were mobile, and 91.4% were single. During a follow-up period of 11+/-22 months, 23 of 26 patients with a prospective diagnosis of CPF that was confirmed by pathological examination had symptoms that could be attributable to embolization. In the group of 45 patients with a presumed diagnosis of CPF, 3 patients had symptoms that were likely due to embolization (incidence, 6.6%) during a follow-up period of 552+/-706 days. CONCLUSIONS: CPFs are generally small and single, occur most often on valvular surfaces, and may be mobile, resulting in embolization. Because of the potential for embolic events, symptomatic patients, patients undergoing cardiac surgery for other lesions, and those with highly mobile and large CPFs should be considered for surgical excision.

Synthesis of a somatostatin-like peptide by Plasmodium falciparum.

The intracellular parasite, Plasmodium falciparum, was found to synthesize a peptide similar to mammalian somatostatin. High performance liquid chromatography of acetic acid extracts of Plasmodium-infected erythrocytes revealed a metabolically labeled peptide that co-eluted with rat somatostatin and that was reactive with antibody against rat somatostatin. Bioassay of partially purified Plasmodium peptide demonstrated somatostatin activity. Acetic acid extracts from non-synchronized infected cultures were shown by radioimmunoassay to contain the equivalent of 150 molecules of somatostatin per parasite. Somatostatin was not detectable in erythrocytes of non-infected cultures.

Analysis of risk factors for development of atrial fibrillation early after cardiac valvular surgery.

Atrial fibrillation (AF) commonly develops after cardiac valvular surgery. The objective of this study was to identify risk factors for postoperative AF following valvular surgery. A cohort of 915 consecutive adult patients undergoing isolated valvular surgery with preoperative sinus rhythm was analyzed. Univariate and independent multivariate risk factors for postoperative AF were determined. A second cohort of 305 patients with the same inclusion criteria was used to validate the multivariate predictors. Patients studied had a mean age of 56.1 +/- 14.7 years, 57.9% were men, 79.6% had a normal left ventricular ejection fraction, and their mean left atrial size was 46.2 +/- 9.3 mm. The incidence of postoperative AF was 36.7%. Independent predictors of postoperative AF included: advanced age (odds ratio [OR] 1.506 per decade, 95% confidence interval, [CI] 1.35 to 1.68, p = 0.0001); mitral stenosis (OR 2.066, CI 1.21 to 3.52, p = 0.0077); left atrial enlargement (OR 1.468, CI 1.07 to 2.01, p = 0.0165); use of systemic hypothermia (OR 0.572, CI 0.422 to 0.776, p = 0.0003); and a history of cardiac surgery (OR 0.676, CI 0.465 to 0.981, p = 0.0393). Among these variables, advanced age, mitral stenosis, and left atrial enlargement were confirmed as independent risk factors in the validation cohort.

Prediction of thrombus-related mechanical prosthetic valve dysfunction using transesophageal echocardiography.

Identification of thrombus-related mechanical prosthetic valve dysfunction (MPVD) has important therapeutic implications. We sought to develop an algorithm, combining clinical and echocardiographic parameters, for prediction of thrombus-related MPVD in a series of 53 patients (24 men, age 52 +/- 16 years) who had intraoperative diagnosis of thrombus or pannus from 1992 to 1997. Clinical and echocardiographic parameters were analyzed to identify predictors of thrombus and pannus. Prevalence of thrombus and diagnostic yields relative to the number of predictors were determined. There were 22 patients with thrombus, 19 patients with pannus, and 12 patients with both. Forty-two of 53 masses were visualized using transesophageal echocardiography (TEE), including 29 of 34 thrombi or both thrombi and panni and 13 of 19 isolated panni. Predictors of thrombus or mixed presentation include mobile mass (p = 0.009), attachment to occluder (p = 0.02), elevated gradients (p = 0.04), and an international normalized ratio of < or = 2.5 (p = 0.03). All 34 patients with thrombus or mixed presentation had > or = 1 predictor. The prevalence of thrombus in the presence of < or = 1, 2, and > or = 3 predictors is 14%, 69%, and 91%, respectively. Thus, TEE is sensitive in the identification of abnormal mass in the setting of MPVD. An algorithm based on clinical and transesophageal echocardiographic predictors may be useful to estimate the likelihood of thrombus in the setting of MPVD. In the presence of > or = 3 predictors, the probability of thrombus is high.

Inferior vena caval masses identified by echocardiography.

The most common cause of an inferior vena caval mass is renal cell carcinoma that extends through the lumen, occurring in 47 of 62 patients (85%). Detection of an inferior vena caval mass affects the surgical approach requiring cardiopulmonary bypass for resection when the mass extends to the heart.

Atrial fibrillation early postoperatively following minimally invasive cardiac valvular surgery.

We report a cohort of our first 100 minimally invasive cardiac valvular operations matched 1:1 by age and valvular surgery type with patients undergoing a traditional midline sternotomy approach. The prevalence of postoperative atrial fibrillation among patients with minimally invasive procedures versus traditional midline sternotomy was 26.3% versus 38.0%, respectively (p = 0.08). Neither multiple logistic regression nor Kaplan-Meier distribution analysis identified differences in postoperative atrial fibrillation between the 2 surgical techniques.

Comparison of tissue harmonic imaging with contrast (sonicated albumin echocardiography and Doppler myocardial imaging for enhancing endocardial border resolution.

Endocardial resolution during 2-dimensional echocardiography is technically limited in at least 10% to 15% of patients. Recently, several ultrasound imaging innovations have been introduced that may improve endocardial resolution and decrease the proportion of technically difficult studies. This study compares tissue harmonic imaging, intravenous sonicated albumin, and Doppler myocardial imaging in patients with technically difficult echocardiograms. Twenty-eight patients with known or suspected cardiac disease and poor baseline endocardial resolution were studied. Only harmonic imaging (conventional and optimized for tissue) was superior to baseline fundamental imaging (p <0.001). Harmonic imaging was superior to baseline imaging in all myocardial regions and in the majority of patients, including those with the worst baseline studies.

Prediction of coronary artery disease in patients undergoing operations for mitral valve degeneration.

OBJECTIVES: We sought to develop and validate a model that estimates the risk of obstructive coronary artery disease in patients undergoing operations for mitral valve degeneration and to demonstrate its potential clinical utility. METHODS: A total of 722 patients (67% men; age, 61 +/- 12 years) without a history of myocardial infarction, ischemic electrocardiographic changes, or angina who underwent routine coronary angiography before mitral valve prolapse operations between 1989 and 1996 were analyzed. A bootstrap-validated logistic regression model on the basis of clinical risk factors was developed to identify low-risk (< or =5%) patients. Obstructive coronary atherosclerosis was defined as 50% or more luminal narrowing in one or more major epicardial vessels, as determined by means of coronary angiography. RESULTS: One hundred thirty-nine (19%) patients had obstructive coronary atherosclerosis. Independent predictors of coronary artery disease include age, male sex, hypertension, diabetes mellitus,and hyperlipidemia. Two hundred twenty patients were designated as low risk according to the logistic model. Of these patients, only 3 (1.3%) had single-vessel disease, and none had multivessel disease. The model showed good discrimination, with an area under the receiver-operating characteristic curve of 0.84. Cost analysis indicated that application of this model could safely eliminate 30% of coronary angiograms, corresponding to cost savings of $430,000 per 1000 patients without missing any case of high-risk coronary artery disease. CONCLUSION: A model with standard clinical predictors can reliably estimate the prevalence of obstructive coronary atherosclerosis in patients undergoing mitral valve prolapse operations. This model can identify low-risk patients in whom routine preoperative angiography may be safely avoided.

Ineffectiveness and potential proarrhythmia of atrial pacing for atrial fibrillation prevention after coronary artery bypass grafting.

BACKGROUND: Atrial pacing is often used empirically to suppress atrial ectopy and prevent atrial fibrillation after coronary artery bypass grafting. METHODS: To determine whether atrial overdrive pacing reduces atrial fibrillation and atrial ectopy after coronary artery bypass grafting, 100 patients were randomized to no atrial pacing (Control) versus AAI pacing at 10 beats/min or more above the resting heart rate (Paced), started by postoperative day 1 and continued through day 4. Major end points were new atrial fibrillation and frequency of atrial ectopy during the first 4 days after coronary artery bypass grafting. RESULTS: Atrial fibrillation occurred by day 4 in 13 of 51 (25.5%) Paced and in 14 of 49 (28.6%) Control patients, p = 0.90. Control patients who developed atrial fibrillation had significantly more atrial ectopy than those who did not. Atrial ectopy was paradoxically more frequent in the Paced group (2,106+/-428 versus 866+/-385 per 24 hours, p = 0.0001). Loss of capture, sensing, and consistent atrial pacing occurred frequently during atrial pacing. CONCLUSIONS: Contrary to prevailing opinion and practice, postoperative atrial overdrive pacing significantly increases atrial ectopy and does not reduce the likelihood of atrial fibrillation.

Intraoperative transesophageal echocardiography in minimally invasive cardiac valve surgery.

The minimally invasive procedure is a new surgical technique that uses a small sternal incision. Because of limited surgical exposure, removal of intracavitary air and visual assessment of cardiac function are not possible. We studied the utility of intraoperative transesophageal echocardiography (IOE) before and after cardiopulmonary bypass in 112 patients (mean age 53.1 +/- 15.2 years, 74 males) who underwent minimally invasive valvular surgery. Surgical procedures included 52 isolated mitral valve procedures (49 repairs, 3 prostheses), 58 isolated aortic valve procedures (16 repairs, 26 prostheses, 16 homografts), and 2 combined aortic and mitral valve repairs. Prepump IOE was useful to confirm valve dysfunction and assist determination of arterial cannulation site. Postpump IOE identified intracardiac air in all patients, which was defined as extensive in 58 (52%) cases. Postoperatively, new left ventricular dysfunction was noted in 22 (20%) patients, more often in the group with extensive air by IOE (17 [30%] of 58 patients) compared with those without extensive air (5 [10%] of 54 patients, P =.01). Second pump runs were required in 7 (6%) of 112 patients: 3 cases of residual aortic regurgitation, 1 case of residual mitral regurgitation, and 3 cases with new ventricular dysfunction. No deaths occurred. We conclude that IOE is essential in minimally invasive valvular surgery because it detects problems that require immediate remedy. IOE allows real-time assessment of ventricular filling, ventricular and valvular function, and intracardiac air.

Right atrial spontaneous echo contrast and thrombi in atrial fibrillation: a transesophageal echocardiography study.

BACKGROUND: Previous studies have reported the clinical and echocardiographic findings of patients with left atrial spontaneous echo contrast (SEC) and thrombi. We sought to study these characteristics in patients with right atrial SEC and thrombi. METHODS: We reviewed 580 consecutive patients from the ACUTE (Assessment of Cardioversion Using Transesophageal Echocardiography) Registry and found 79 patients (14%, aged 67 +/-13 years, 67 male) with transesophageal echocardiography (TEE) findings of right atrial SEC or thrombi (group 1). This group was compared with a control group of 75 consecutive patients (group 2) (aged 68 +/- 13 years, P = not significant; 49 male, P <.005) from the registry with no TEE findings of SEC or thrombi in the left or right atrium. RESULTS: Atrial fibrillation was present in 60 of 79 group 1 patients (76%). Five right atrial (6%) and 11 left atrial (14%) thrombi were identified. Both left ventricular ejection fraction (39% +/- 16% versus 47% +/- 14%; P =.0005) and presence of right ventricular dysfunction (n = 44 versus 18; P =.0001) differed significantly between groups 1 and 2, respectively. Right atrial area (24 +/- 6 cm(2) versus 22 +/- 6 cm(2); P = .02) was larger in patients in group 1. Left atrial SEC was present in 68 of 79 group 1 patients (86%). Patients with right atrial thrombi and right atrial SEC had a longer duration of arrhythmia (524 +/-812 days versus 147 +/-368 days, P <.05) than patients with right atrial SEC only. CONCLUSIONS: Right atrial SEC has a prevalence of 14% in patients with atrial arrhythmia who undergo TEE-guided cardioversion. Right atrial thrombi are a rare finding and were seen in fewer than 1% (5/580) of patients with atrial arrhythmia. Right atrial thrombi among patients on anticoagulation therapy were not associated with clinically significant pulmonary embolism.

Calculation of mitral regurgitant orifice area with use of a simplified proximal convergence method: initial clinical application.

To validate a previously proposed simplified proximal flow convergence method for calculating mitral regurgitant orifice area (ROA), a prospective study was conducted in ambulatory patients and in patients undergoing open heart surgery. Assuming a pressure difference between the left ventricle and left atrium of approximately 100 mm Hg (jet velocity [v(p)] 500 cm/s) and setting the color aliasing velocity (v(a)) to 40 cm/s, we simplified the conventional proximal convergence method formula (ROA = 2pi(r2)v(a)/v(p)) to r2/2, where r is the radius of the proximal convergence isovelocity hemisphere. For 57 ambulatory patients with a wide range of mitral regurgitant severity (1 to 4+), ROA was calculated by the conventional (x) and simplified (y) methods, demonstrating excellent accuracy (r = 0.92; P <.001; DeltaROA [y - x] = 0.004 +/- 0.08 cm2). For 24 intraoperative patients, ROA calculated by the simplified formula (y) correlated well with the pulsed Doppler-thermodilution method (x) (r = 0.84; P <.01; DeltaROA [y - x] = -0.002 +/- 0.08cm2). This simplified proximal convergence formula yields an accurate assessment of ROA for a wide range of regurgitant severity, while the time required for this measurement is shortened by half (1.5 +/- 0.5 minutes versus 3.2 +/- 0.7 minutes). This may increase the frequency of calculating ROA in the clinical laboratory.

Arrhythmogenic right ventricular cardiomyopathy: a cause of sudden death in young people.

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an increasingly recognized cause of ventricular tachycardia and sudden cardiac death in young people, notably young athletes. The best treatment is not clear, although options include antiarrhythmic drugs, radiofrequency ablation, and implantable defibrillators.

Effects of hyperthermia on the membrane potential and Na+ transport of V79 fibroblasts.

The effects of hyperthermia (41-43 degrees C) on the membrane potential (calculated from the transmembrane distribution of [3H]tetraphenylphosphonium) and Na+ transport of Chinese hamster V79 fibroblasts were studied. At 41 degrees C, hyperthermia induced a membrane hyperpolarization of log phase cells (5 to 26 mV) that was reversible upon returning to 37 degrees C. The hyperpolarization was inhibited 50% by 1 mM ouabain or 0.25 mM amiloride, an inhibitor of Na+:H+ exchange. Shifting temperature to 41 degrees C increased ouabain-sensitive Rb+ uptake indicating activation of the electrogenic Na+ pump. At 43 degrees C for 60 min, the membrane potential of log phase cells depolarized (20-35 mV). Parallel studies demonstrated enhanced Na+ uptake at 41 degrees C only in the presence of ouabain. At 43 degrees C, Na+ uptake was increased relative to controls with or without ouabain present. At both 41 and 43 degrees C, 0.25 mM amiloride inhibited heat-stimulated Na+ uptake. Na+ efflux was enhanced at 41 degrees C in a process inhibited by ouabain. Thus, one consequence of heat treatment at 41 degrees C is activation of Na+:H+ exchange with the resultant increase in cytosolic [Na+] activating the electrogenic Na+ pump. At temperatures greater than or equal to 43 degrees C, the Na+ pump is inhibited.

Insights into the pathophysiology of atherosclerosis and prognosis of black Americans with acute coronary syndromes.

BACKGROUND: Disparities in prognosis for black and white patients with coronary heart disease have been widely reported. For several reasons it is unclear to what extent biologic factors contribute to these differences. METHODS: The current medical literature regarding the pathophysiologic characteristics of cardiovascular disease is reviewed with emphasis on how racially mediated biologic differences may affect the manifestation, treatment, and prognosis of patients with coronary heart disease, particularly patients with acute coronary syndromes. RESULTS: Black patients with coronary heart disease have a higher prevalence of ischemic heart disease risk factors, including hypertension, left ventricular hypertrophy, diabetes, and tobacco use. Other factors related to atherosclerosis, vascular reactivity, and thrombolysis that quantitatively and functionally differ among racial groups are identified. Prospective, randomized trials comparing outcomes among patients with acute coronary syndromes have included only a fraction of the available black population, although they reveal a similar short-term mortality rate for black and white patients. Several factors, including enhanced fibrinolysis among black patients with acute myocardial infarction, may in part counterbalance better understood and more prevalent comorbidities to equalize short-term (30-day) survival. All-cause, long-term (1-year) mortality appears worse for black patients compared with white patients with similar cardiovascular risk profiles. CONCLUSION: As racially mediated biologic differences between black and white patients become better understood, targeted interventions to prevent coronary heart disease and treat acute coronary syndromes in black patients can be developed.

Long-term follow-up of gender-specific outcomes after thrombolytic therapy for acute myocardial infarction from the GUSTO-I trial. Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries.

Our objective was to assess gender differences in mortality 1 year after acute myocardial infarction (MI). The Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO-I) trial database of 41,021 patients with suspected acute MI was used to generate 1-year Kaplan-Meier survival plots. Risk quartiles and mortality of women and men were compared. The unadjusted 1-year mortality rate for the initial GUSTO-I population and 30-day survivors demonstrates a large gender gap [odds ratio for all patients = 2.2, 95% confidence interval (CI), 2.0-2.3, p < 0.001]. For the initial population, when adjusted for age, the gender gap is still apparent (odds ratio = 1.4, 95%, CI = 1.3-1.5, p < 0.001) although no longer significant when adjusted using the 30-day survival model (odds ratio = 1.06, 95% CI = 0.97-1.15, p < 0.001). For the 30-day survivors, adjustment based on age alone explained the 1-year mortality difference (risk ratio = 0.96, 95% CI 0.85-1.07, p = 0.441). When the population was divided into expected risk quartiles, women were more likely to fall into the higher expected risk quartiles, even after adjusting for age. A gender gap after acute MI is apparent, nearly all of which occurs within the first 30 days. A substantial portion of the gender gap is explained by the increased age of women, and the rest of the gap may be attributed to differences in variables predictive of 30-day mortality. During 1-year follow-up, the late mortality of women is no greater than that of age-matched men.

Efficacy of anticoagulation in resolving left atrial and left atrial appendage thrombi: A transesophageal echocardiographic study.

BACKGROUND: Transesophageal echocardiography (TEE) is the gold standard for evaluation of the left atrium and the left atrial appendage (LAA) for the presence of thrombi. Anticoagulation is conventionally used for patients with atrial fibrillation to prevent embolization of atrial thrombi. The mechanism of benefit and effectiveness of thrombi resolution with anticoagulation is not well defined. METHODS AND RESULTS: We used a TEE database of 9058 consecutive studies performed between January 1996 and November 1998 to identify all patients with thrombi reported in the left atrium and/or LAA. One hundred seventy-four patients with thrombi in the left atrial cavity (LAC) and LAA were identified (1.9% of transesophageal studies performed). The incidence of LAA thrombi was 6.6 times higher than LAC thrombi (151 vs 23, respectively). Almost all LAC thrombi were visualized on transthoracic echocardiography (90.5%). Mitral valve pathology was associated with LAC location of thrombi (P <.0001), whereas atrial fibrillation or flutter was present in most patients with LAA location of thrombi. Anticoagulation of 47 +/- 18 days was associated with thrombus resolution in 80.1% of the patients on follow-up TEE. Further anticoagulation resulted in limited additional benefit. CONCLUSIONS: LAC thrombi are rare and are usually associated with mitral valve pathology. Transthoracic echocardiography is effective in identifying these thrombi. LAA thrombi occur predominantly in patients with atrial fibrillation or flutter. Short-term anticoagulation achieves a high rate of resolution of LAA and LAC thrombi but does not obviate the need for follow-up TEE.