Natural history of a systemic right ventricle.

The natural history of a systemic right ventricle after an atrial switch procedure has yet to be fully characterised. We describe the case of the longest surviving patient at our institution who underwent a Mustard Baffle correction for dextro-transposition of great arteries in childhood. Over following decades he was reviewed regularly with deteriorating systemic right ventricle function. At around 50 years of age he developed worsening heart failure on maximal medical therapy. He was subsequently assessed for cardiac transplantation which he underwent successfully at the age of 55 years.

Intraoperative transesophageal echocardiography for surgical repair of mitral regurgitation.

Surgical repair of the mitral valve is being increasingly performed to treat severe mitral regurgitation. Transesophageal echocardiography is an essential tool for assessing valvular function and guiding surgical decision making during the perioperative period. A careful and systematic transesophageal echocardiographic examination is necessary to ensure that appropriate information is obtained and that the correct diagnoses are obtained before and after repair. The purpose of this article is to provide a practical guide for perioperative echocardiographers caring for patients undergoing surgical repair of mitral regurgitation. A guide to performing a systematic transesophageal echocardiographic examination of the mitral valve is provided, along with an approach to prerepair and postrepair assessment. Additionally, the anatomy and function of normal and regurgitant mitral valves are reviewed.

Thrombo-embolic cerebral infarction secondary to giant Lambl's excrescence.

Lambl's excrescences are common fibrinous strands found at the contact margin of cardiac valves. They are referred to as "giant" when multiple strands form a complex. Embolic stroke secondary to these valvular strands has rarely been described in the literature. We present a patient with recurrent thrombo-embolic cerebral infarction secondary to giant Lambl's excrescence successfully treated with anticoagulation.

Plasma B-type natriuretic peptide levels in cardiac donors.

INTRODUCTION: Elevated levels of plasma brain natriuretic peptide (BNP) and amino-terminal BNP (NT-proBNP) are associated with adverse cardiac outcomes. It is not known whether BNP and NT-proBNP levels in heart donors can aid in selection and predict outcomes in transplant recipients. METHODS: Plasma BNP and NT-proBNP were measured in 32 organ donors prior to removal from life-support systems. Twelve hearts were accepted and 20 hearts were declined (no suitable recipient - 12, probable coronary artery disease - four, abnormal echocardiogram - three, other medical reasons - one). Records of heart transplant recipients were reviewed for: survival at 30 d, length of intensive care stay and need for intra-aortic balloon counter-pulsation (IABP). RESULTS: Donors were divided into three groups - Group 1 (n = 12): accepted hearts; Group 2 (n = 12): acceptable hearts not transplanted for logistic reasons; Group 3 (n = 8): declined because of probable cardiac disease. BNP and NT-proBNP levels were significantly lower in donors with acceptable hearts (n = 24) compared with those with unacceptable hearts (n = 8) (p = 0.02 and 0.032, respectively). Of the 12 patients transplanted, four suffered a suboptimal outcome (two died, one required inotropic support and IABP, one prolonged hospitalization) while eight had good outcomes with no significant difference in BNP/NT-proBNP levels between these groups. CONCLUSION: BNP and NT-proBNP levels were lower in organ donors whose hearts were acceptable for transplantation compared with those whose hearts were unsuitable. Measuring natriuretic peptides may be a useful adjunctive tool in the selection of donor hearts. We feel that further studies are warranted.

Percutaneous transcatheter obliteration of aortic paravalvular leak.

A 76-year-old man who underwent aortic valve replacement for severe calcific aortic stenosis developed a significant paravalvular leak. Because the risk of re-operation was felt too great, a percutaneous transcatheter obliteration of the defect using an Amplatzer vascular plug was undertaken, with an excellent clinical outcome.

Association of the fourth heart sound with increased left ventricular end-diastolic stiffness.

BACKGROUND: Although the fourth heart sound (S4) is thought to be associated with a stiff left ventricle, this association has never been proven. Recently, single-beat estimation of the end-diastolic pressure volume relationship (EDPVR) has been characterized (P = alphaV(beta)), allowing the estimation of EDPVR in larger groups of patients. We hypothesized that the S(4) is associated with an upward- and leftward-shifted EDPVR, indicative of elevated end-diastolic stiffness. METHODS AND RESULTS: Ninety study participants underwent acoustic cardiographic analysis, echocardiography, and left heart catheterization. We calculated alpha and beta coefficients to define the nonlinear slope of the EDPVR using the single-beat method for measuring left ventricular end-diastolic elastance. In the P = alphaV(beta) EDPVR estimation, alpha was similar (P = .31), but beta was significantly higher in the S(4) group (5.96 versus 6.51, P = .002), signifying a steeper, upward- and leftward-shifted EDPVR curve in subjects with an S(4). The intensity of the S(4) was associated with both beta (r = 0.42, P < .0001) and E/E' / stroke volume index, another index of diastolic stiffness (r = 0.39, P = .0008). On multivariable analysis, beta remained associated with the presence (P = .008) and intensity (P < .0001) of S(4) after controlling for age, sex, and ejection fraction. CONCLUSIONS: The S(4) is most likely generated from an abnormally stiff left ventricle, supporting the concept that the S(4) is a pathologic finding in older patients.

Physiology of the third heart sound: novel insights from tissue Doppler imaging.

BACKGROUND: The third heart sound (S(3)) is thought to be caused by the abrupt deceleration of left ventricular (LV) inflow during early diastole, increased LV filling pressures, and decreased LV compliance. We sought to determine whether the ratio of early mitral inflow velocity to diastolic velocity of the mitral annulus (E/E') could confirm the proposed mechanism of the S(3). METHODS: A total of 90 subjects underwent phonocardiography, echocardiography, tissue Doppler imaging, and left-sided heart catheterization. RESULTS: Phonocardiography detected an S(3) in 21 patients (23%). Subjects with an S(3) had lower ejection fraction (P = .0006) and increased E deceleration rate (P < .0001), E/E' (P < .0001) and filling pressures (P < .0001). The phonocardiographic S(3) confidence score correlated with E/E' (r = 0.46; P < .0001) and E deceleration rate (r = 0.43, P = .0001). Of the echocardiographic variables, only E/E' was independently associated with the S(3) confidence score (P = .009), independently of invasively determined LV filling pressures (P = .001). CONCLUSIONS: The most important determinants of the pathologic S(3) are an increased deceleration rate of early mitral inflow, elevated LV filling pressures, and abnormal compliance of the myocardium as measured by tissue Doppler imaging.

Quantitative assessment of severity of mitral regurgitation by serial echocardiography in a multicenter clinical trial of percutaneous mitral valve repair.

The aims of the echocardiographic substudy of this multicenter trial were to evaluate the use of quantitative assessment of mitral regurgitation (MR) severity using serial echocardiography and to assess the efficacy of percutaneous mitral valve repair. Previous surgical repair studies did not use quantitative echocardiographic methods. Results of a percutaneous mitral valve repair clip device in a core echocardiographic laboratory were evaluated. Published parameters for quantifying MR were used in a systematic protocol to qualify patients for study entry and evaluate treatment efficacy at discharge and 6 months after clip repair. Baseline results were presented for 55 patients, and follow-up results, for 49. Ninety-eight percent of required echocardiographic studies were submitted to the core laboratory, and >85% of required measurements were possible. At baseline, mean regurgitant volume was 54.8 +/- 24 ml, regurgitant fraction was 46.9 +/-16.2%, effective regurgitant orifice area was 0.71 +/- 0.40 cm(2), and vena contracta width was 0.66 +/- 0.20 cm. Based on a severity scale of 1 to 4, mean color flow grade was 3.4 +/- 0.7, and mean pulmonary vein flow was 2.8 +/- 1.2. In patients with a clip at 6 months, all measurements of MR severity were significantly decreased versus baseline, with mean regurgitant volume decreased from 50.3 to 27.5 ml (change -22.8 ml; p <0.0001), regurgitant fraction from 44.6% to 28.9% (change -15.7%; p <0.0001), color flow grade from an average of 3.4 to 1.8 (change -1.6; p <0.0001), and pulmonary vein flow from 2.8 to 1.8 (change -1.0; p <0.0018). In conclusion, quantitative assessment of MR is feasible in a multicenter trial, and percutaneous mitral repair with the MitraClip produces a sustained decrease in MR severity to moderate or less for > or =6 months.

Performance of phonoelectrocardiographic left ventricular systolic time intervals and B-type natriuretic peptide levels in the diagnosis of left ventricular dysfunction.

BACKGROUND: Systolic time intervals measured by echocardiography and carotid artery tracings are validated methods of assessing left ventricular function. However, the clinical utility of phonoelectrocardiographic systolic time intervals for predicting heart failure using newer technology has not been evaluated. METHODS: We enrolled 100 adult patients undergoing left heart catheterization. Participants underwent computerized phonoelectrocardiographic analysis, left ventricular end-diastolic pressure (LVEDP) measurement, transthoracic echocardiographic measurement of left ventricular ejection fraction (LVEF), and B-type natriuretic peptide (BNP) testing. The heart rate-adjusted systolic time intervals included the time from the Q wave onset to peak S1 (electromechanical activation time, EMAT), Q wave onset to peak S2 (electromechanical systole, Q-S2), and peak S1 to peak S2 (left ventricular systolic time, LVST). Left ventricular dysfunction was defined as the presence of both LVEDP >15 mmHg and LVEF <50%. RESULTS: EMAT (r =-0.51; P < 0.0001), EMAT/LVST (r =-0.41; P = 0.0001), and Q-S2 (r =-0.39; P = 0.0003) correlated with LVEF, but not with LVEDP. An abnormal EMAT > or =15 (odds ratio 1.38, P < 0.0001) and EMAT/LVST > or =0.40 (OR 1.13, P = 0.002) were associated with left ventricular dysfunction. EMAT > or =15 had 44% sensitivity, 94% specificity, and a 7.0 likelihood ratio for left ventricular dysfunction, while EMAT/LVST > or =0.40 had 55% sensitivity, 95% specificity, and a 11.7 likelihood ratio. In patients with an intermediate BNP (100-500 pg/mL), the likelihood ratio increased from 1.1 using the BNP result alone to 11.0 when adding a positive EMAT test for predicting left ventricular dysfunction. CONCLUSIONS: Phonoelectrocardiographic measures of systolic time intervals are insensitive but highly specific tests for detecting abnormalities in objective markers of left ventricular function. EMAT and EMAT/LVST provide diagnostic information independent of BNP for detecting patients with left ventricular dysfunction.

Diagnostic characteristics of combining phonocardiographic third heart sound and systolic time intervals for the prediction of left ventricular dysfunction.

BACKGROUND: The third heart sound (S3) and systolic time intervals (STIs) are validated clinical indicators of left ventricular (LV) dysfunction. We investigated the test characteristics of a combined score summarizing S3 and STI results for predicting LV dysfunction. METHODS AND RESULTS: A total of 81 adults underwent computerized phonelectrocardiography for S3 and STI (Audicor, Inovise Medical Inc), cardiac catheterization for LV end-diastolic pressure (LVEDP), echocardiography for LV ejection fraction (LVEF), and B-type natriuretic peptide (BNP) testing. LV dysfunction was defined as both an LVEDP >15 mm Hg and LVEF <50%. The STI measured was the electromechanical activation time (EMAT) divided by LV systolic time (LVST). Z-scores for the S3 confidence score and EMAT/LVST were summed to generate the LV dysfunction index. The LV dysfunction index had a correlation coefficient of 0.38 for LVEDP (P = .0003), -0.53 for LVEF (P < .0001), and 0.35 for BNP (P = .0008). This index had a receiver operative curve c-statistic of 0.89 for diagnosis of LV dysfunction; a cutoff >1.87 yielded 72% sensitivity, 92% specificity, 9.0 positive likelihood ratio, and 88% accuracy. CONCLUSIONS: In this preliminary study, the LV dysfunction index combined S3 and STI data from noninvasive electrophonocardiography, and yielded superior test characteristics compared to the individual tests for the diagnosis of LV dysfunction.

Obese patients have lower B-type and atrial natriuretic peptide levels compared with nonobese.

Obesity is a risk factor for the development of heart failure, but the causal mechanism remains unclear. Impaired production or enhanced clearance of natriuretic peptides, which regulate sodium balance and sympathetic activation, may play an important role. The authors investigated the relationship of plasma B-type natriuretic peptide and atrial natriuretic peptide levels to body mass index in 100 patients referred for left heart catheterization. Hemodynamic and echocardiographic data were obtained for all study participants. Atrial natriuretic peptide and B-type natriuretic peptide levels were compared in obese (body mass index > or = 30 kg/m2) and nonobese (body mass index < 30 kg/m2) subjects. Multivariate regression analyses were performed, adjusting for clinical and hemodynamic covariates. Obese patients had significantly lower B-type natriuretic peptide (p = 0.03) and atrial natriuretic peptide (p = 0.04) levels compared with nonobese. Multivariate analysis revealed lower B-type natriuretic peptide (p = 0.095) and atrial natriuretic peptide (p = 0.007) levels in obese patients while controlling for age, sex, left ventricular end-diastolic pressure, and left ventricular ejection fraction. Low levels of circulating natriuretic peptides are thus associated with obesity and may contribute to the development of heart failure.

Relationship between accurate auscultation of a clinically useful third heart sound and level of experience.

BACKGROUND: Poor performance by physicians-in-training and interobserver variability between physicians have diminished clinicians' confidence in the value of the third heart sound (S3). METHODS: To determine whether auscultation of a clinically useful S3 improves with advancing levels of experience, we performed a prospective, blinded, observational study of 100 patients undergoing left-sided heart catheterization. Patients underwent blinded auscultation by 4 physicians (each from 1 of 4 different levels of experience), phonocardiography, measurement of blood B-type natriuretic peptide levels, echocardiography for measurement of left ventricular ejection fraction, and cardiac catheterization for measurement of left ventricular end-diastolic pressure. RESULTS: Whereas residents' and interns' auscultatory findings demonstrated no significant agreement with phonocardiographic findings, an S3 auscultated by cardiology fellows (kappa = 0.37; P<.001) and cardiology attendings (kappa = 0.29; P = .003) agreed with phonocardiographic findings. Although the sensitivities of the S3 were low (13%-52%) for identifying patients with abnormal measures of left ventricular function, the specificities were high (85%-95%), with the best test characteristics exhibited by phonocardiography and more experienced physicians. The S3 detected by attendings and fellows was superior in distinguishing an elevated B-type natriuretic peptide level, a depressed left ventricular ejection fraction, or an elevated left ventricular end-diastolic pressure (P = .002-.02 for attendings and .02-.03 for fellows) compared with residents (P = .02-.47) or interns (P = .09-.64). CONCLUSIONS: The S3 auscultated by more experienced physicians demonstrated fair agreement with phonocardiographic findings. Although correlations were superior for phonocardiography, the associations between the S3 and abnormal markers of left ventricular function improved with each level of auscultator experience.

High-sensitivity C-reactive protein and parameters of left ventricular dysfunction.

BACKGROUND: Elevated levels of high-sensitivity C-reactive protein (CRP), an inflammatory marker, have been associated with heart failure. However, it is not known which parameters of left ventricular dysfunction correlate with elevated levels of CRP. METHODS AND RESULTS: In this cross-sectional study of 98 patients referred for cardiac catheterization, we investigated whether commonly used clinical indices of left ventricular dysfunction correlated with CRP levels. CRP levels were elevated to a greater degree in participants with diabetes mellitus (P =.006) and heart failure (P =.003). Increased CRP levels were associated with increased plasma levels of B-type natriuretic peptide (BNP; P =.0001), decreased left ventricular ejection fraction (LVEF; P =.02), and increased left-ventricular end-diastolic pressure (LVEDP; P =.0005). After multivariable adjustment, LVEDP and CRP were independently associated (P =.046). CONCLUSION: CRP is increased in patients with heart failure. Of the clinical parameters of left ventricular dysfunction, direct measurement of left ventricular end-diastolic pressure is most closely associated with CRP.

Association between phonocardiographic third and fourth heart sounds and objective measures of left ventricular function.

CONTEXT: The third (S3) and fourth (S4) heart sounds detected by phonocardiography are considered to represent the criterion standards of the gallop sounds, but their test characteristics have not been explored. OBJECTIVE: To determine the diagnostic test characteristics of the S3 and S4 for prediction of left ventricular dysfunction using a computerized heart sound detection algorithm. DESIGN, SETTING, AND PARTICIPANTS: Prospective study of 90 adult patients undergoing elective left-sided heart catheterization at a single US teaching hospital between August 2003 and June 2004. The mean age was 62 (SD, 13) years (range, 24-90 years) and 61 (68%) were male. Within a 4-hour period, participants underwent computerized heart sound phonocardiographic analysis, cardiac catheterization, transthoracic echocardiography, and blood sampling for assessment of an S3/S4, left ventricular end-diastolic pressure (LVEDP), left ventricular ejection fraction (LVEF), and B-type natriuretic peptide (BNP), respectively. MAIN OUTCOME MEASURES: Diagnostic test characteristics of the computerized phonocardiographic S3 and S4 using markers of left ventricular function as criterion standards. RESULTS: Mean (SD) LVEDP was significantly elevated (18.4 [6.9] mm Hg vs 12.1 [7.3] mm Hg; P<.001), mean (SD) LVEF was reduced (49.4% [20.2%] vs 63.6% [14.8%]; P<.001), and median (interquartile range) BNP was elevated (330 [98-1155] pg/mL vs 86 [41-192] pg/mL; P<.001) in those with an S3, S4, or both compared with patients without a diastolic heart sound. The sensitivities of these heart sounds to detect an elevated LVEDP, reduced LVEF, or elevated BNP were 41%, 52%, and 32% for an S3, and 46%, 43%, and 40% for an S4, respectively. For abnormal levels of the same markers of ventricular function, the specificities of the S3 were 92%, 87%, and 92%, while the specificities of the S4 were 80%, 72%, and 78%, respectively. CONCLUSIONS: Neither the phonocardiographic S3 nor the S4 is a sensitive marker of left ventricular dysfunction. The phonocardiographic S3 is specific for left ventricular dysfunction and appears to be superior to the moderate specificity of the phonocardiographic S4.

Effects of intravenous levosimendan on human coronary vasomotor regulation, left ventricular wall stress, and myocardial oxygen uptake.

BACKGROUND: Levosimendan is a calcium-sensitizing agent and an inodilator under current investigation in the treatment of decompensated heart failure. The effects of intravenous levosimendan on the human coronary vasculature, together with myocardial wall stress and oxygen uptake, have not been adequately studied. METHODS AND RESULTS: Ten adult patients underwent right- and left-heart catheterization. Baseline coronary blood flow was determined with quantitative coronary angiography and an intracoronary Doppler-tipped guidewire. Myocardial oxygen uptake was measured with a coronary sinus catheter. Echocardiography was performed before and 30 minutes after an intravenous infusion of levosimendan (24-microg/kg bolus over 10 minutes) was begun. Pulmonary capillary wedge decreased 37% (P=0.009), cardiac output increased 9% (P=0.04), and systemic vascular resistance decreased 18% (P<0.001). Left ventricular ejection fraction increased 20% (P=0.009), and meridional systolic wall stress decreased 48% (P=0.009). Coronary artery diameter increased 10% at 15 minutes (P=0.001) and 11% at 30 minutes (P=0.01). Coronary artery velocity increased 10% over baseline (P=0.04). Coronary blood flow increased 45% (P=0.02), whereas coronary resistance decreased 36% at 30 minutes (P=0.03). Myocardial oxygen extraction decreased 9% at 30 minutes (P=0.04). CONCLUSIONS: Levosimendan given intravenously exerts vasodilator effects on human coronary conductance and resistance arteries. Despite a decrease in coronary perfusion pressure, coronary blood flow is increased. A reduction in coronary vascular resistance and a decrease in coronary venous oxygen content indicate primary coronary vasodilation by levosimendan. Improved left ventricular systolic function and decreased myocardial oxygen extraction suggest improved myocardial efficiency.

Usefulness of serial measurement of N-terminal pro-brain natriuretic peptide plasma levels in asymptomatic patients with aortic stenosis to predict symptomatic deterioration.

In 29 initially asymptomatic patients with aortic stenosis followed for an average of 18 months, patients with a N-terminal pro-brain natriuretic peptide (NT-pro-BNP) level above the normal range at baseline were more likely to develop symptoms during follow-up compared with patients with NT-pro-BNP within normal limits. The average increase in NT-pro-BNP per year was greater for patients who developed symptoms compared with patients who remained asymptomatic. Aortic valve area, peak aortic velocity, and the ejection fraction were less reliable predictors of symptom onset. Measurement of NT-pro-BNP in addition to clinical assessment and echocardiography may allow more reliable follow-up and timing of valve replacement for aortic stenosis.