Auscultatory and phonocardiographic manifestations of pulmonary hypertension

Predicting the Origin of Ventricular Arrhythmia Using Acoustic Cardiography

This study aimed to examine the relationship between measurements related to heart sounds and the origin of ventricular arrhythmia. We retrospectively evaluated 45 patients undergoing catheter ablation with contemporaneous digital acoustic cardiography of the first heart sound (S1) and the second heart sound (S2). The patients with baseline wide QRS morphology (>120 ms or aberrant conduction), heart failure, valvular heart disease, chronic pulmonary disease, and obesity were excluded. Ventricular arrhythmias from the left ventricle had an increased S1 complexity score and S1 duration in comparison to adjacent sinus beats. On the other hand, ventricular arrhythmia from right ventricle had decreased S1 complexity score and S1 duration in comparison to adjacent sinus beats. The difference of S1 (ΔS1) parameters between premature ventricular complex and sinus beat was significantly smaller in right ventricular arrhythmia group compared with and left ventricular arrhythmia group. For predicting the origin of ventricular arrhythmia, the ΔS1 duration provide better predictive accuracy (sensitivity: 100%, specificity: 100%, cutoff value: −1.28 ms) in comparison to ΔS1 complexity score (sensitivity 71.4%, specificity 75.0%, cutoff value: −0.13). The change of S1 complexity and duration determined from acoustic cardiography could accurately predict the ventricular arrhythmia origin.

Haemodynamic and structural correlates of the first and second heart sounds in pulmonary arterial hypertension: an acoustic cardiography cohort study

OBJECTIVE

To examine the relationship between acoustic characteristics of the first and second heart sounds (S1 and S2) and underlying cardiac structure and haemodynamics in patients with isolated pulmonary arterial hypertension (PAH) and controls.

DESIGN

Prospective multicentre cohort study.

SETTING

Tertiary referral and community hospitals.

PARTICIPANTS

We prospectively evaluated 40 PAH patients undergoing right-heart catheterisation with contemporaneous digital acoustic cardiography (intensity and complexity) and two-dimensional transthoracic echocardiography. To normalise for differences in body habitus, acoustic variables were also expressed as a ratio (S2/S1). 130 participants (55 also had haemodynamic and/or echocardiographic assessment) without clinical or haemodynamic evidence of PAH or congestive heart failure acted as controls.

RESULTS

Patients with PAH had higher mean pulmonary artery pressure (mPA; 40±13 vs 16±4 mm Hg, p<0.0001) and pulmonary vascular resistance (9±6 vs 1±1 Wood Units, p<0.0001) compared with controls, but cardiac index and mean pulmonary capillary wedge pressure were similar. More PAH patients had evidence of right ventricular (RV) dilation (50% vs 19%) and RV systolic dysfunction (41% vs 9%) in the moderate-severe range (all p<0.05). Compared with controls, the acoustic profiles of PAH patients were characterised by increased S2 complexity, S2/S1 complexity and S2/S1 intensity (all p<0.05). In the PAH cohort, S2 complexity was inversely related to S1 complexity. mPA was the only independent multivariate predictor of S2 complexity. The severity of RV enlargement and systolic impairment had reciprocal effects on the complexity of S2 (increased) and S1 (decreased). Decreased S1 complexity was also related to evidence of a small left ventricular cavity.

CONCLUSIONS

Acoustic characteristics of both S1 and S2 are related to the severity of PAH and are associated with RV enlargement and systolic dysfunction. The reciprocal relationship between S2 and S1 complexity may also reflect the underlying ventricular interaction associated with PAH.

Rheumatic mitral stenosis. On the rise again

Rheumatic mitral stenosis remains an important cause of exertional dyspnea, pulmonary congestion, atrial fibrillation, and stroke. Detection rests on careful auscultatory examination and detailed review of chest films. Diagnosis is confirmed by echocardiographic examination; cardiac catheterization is important in symptomatic patients to evaluate the severity of stenosis and associated lesions. Treatment of pulmonary congestion and control of heart rate in patients with atrial fibrillation remain major medical goals. Percutaneous balloon commissurotomy is preferred for most patients with predominant mitral stenosis and for those with contraindications to valve replacement. Implantation of a prosthetic valve is best for patients with significant mitral regurgitation, multivalve disease, associated coronary artery disease that requires bypass, or mitral valve deformity too severe to allow adequate balloon commissurotomy.

Doppler assessment of interventricular pressure gradient across isolated ventricular septal defect

Continuous wave Doppler ultrasound was used to estimate the pressure gradient between the right and left ventricle for assessment of pulmonary arterial systolic pressure in 30 patients with isolated ventricular septal defect and for subsequent comparison with similar data obtained on cardiac catheterization. The age of the patients ranged from 8 months to 45 years (6.8 +/- 8.6 years). No patient had right or left ventricular outflow tract obstruction. Doppler measurements were done within 24 h of cardiac catheterization. Pressure gradient across ventricular septal defect on cardiac catheterization ranged from 7 to 95 mmHg (48 +/- 24 mmHg) and that on Doppler assessment ranged from 8 to 78 mmHg (42 +/- 20 mmHg). Doppler measurements of interventricular pressure gradient correlated well with those obtained on cardiac catheterization (r = 0.90, p less than 0.001). Correlation was better in patients with pressure gradient across ventricular septal defect less than 75 mmHg (r = 0.96). Correlation was poor in three of five patients with very small ventricular septal defects (interventricular pressure gradient greater than 75 mmHg) because the jet used was not ideal. Thus continuous wave Doppler ultrasound is an accurate noninvasive means of measuring pressure gradient across ventricular septal defect, which is a useful parameter for assessment of pulmonary artery systolic pressure in patients with isolated ventricular septal defect without right and left ventricular outflow tract obstruction.

Primary pulmonary hypertension in adults

Primary pulmonary hypertension is an enigmatic disease found predominantly in young women, but it also affects a significant number of middle-aged and elderly males and females. Its onset, characterized by progressively worsening dyspnea, fatigue, and chest pain, is insidious. Three distinct histopathologic subtypes have been identified, and the natural history of the disease process has been well-defined. Pharmacologic treatment options have, in general, been disappointing, and it appears that heart-lung transplantation will be applied only to a small minority of young patients with primary pulmonary hypertension in the near future. We review the histopathology, evaluation, treatment, and prognosis of primary pulmonary hypertension.

Quantitative assessment of pulmonary hypertension in patients with rheumatic heart disease using continuous wave Doppler ultrasound

The accuracy of Doppler ultrasound in estimating pulmonary arterial systolic pressure non-invasively was evaluated in 50 patients with rheumatic heart disease. In all cases, the maximal velocity of the tricuspid regurgitation jet was measured by continuous wave Doppler ultrasound and the systolic pressure gradient between right ventricle and the right atrium was calculated by the modified Bernoulli equation. There was a close correlation between Doppler estimated and hemodynamically measured transtricuspid systolic gradient (r = 0.86, P less than 0.001). Right ventricular systolic pressure, which equals pulmonary arterial systolic pressure in the absence of right ventricular outflow obstruction, was calculated by adding a constant of 10 to the Doppler gradient and also by using a regression equation. Right ventricular systolic pressure obtained by both of these Doppler methods correlated closely with values at cardiac catheterization (r = 0.82 and 0.83, respectively). Our study suggests that pulmonary arterial systolic pressure can be determined non-invasively with accuracy, by Doppler ultrasound, in patients with rheumatic heart disease.

Comparison of three Doppler ultrasound methods in the prediction of pulmonary artery pressure

Pulmonary artery pressure was noninvasively estimated by three Doppler echocardiographic methods in 50 consecutive patients undergoing cardiac catheterization. First, a systolic transtricuspid gradient was calculated from Doppler-detected tricuspid regurgitation; clinical jugular venous pressure or a fixed value of 14 mm Hg was added to yield systolic pulmonary artery pressure. Second, acceleration time from pulmonary flow analysis was used in a regression equation to derive mean pulmonary artery pressure. Third, right ventricular isovolumic relaxation time was calculated from Doppler-determined pulmonary valve closure and tricuspid valve opening; systolic pulmonary artery pressure was then derived from a nomogram. In 48 patients (96%) at least one of the methods could be employed. A tricuspid pressure gradient, obtained in 36 patients (72%), provided reliable prediction of systolic pulmonary artery pressure. The prediction was superior when 14 mm Hg rather than estimated jugular venous pressure was used to account for right atrial pressure. In 44 patients (88%), pulmonary flow was analyzed. Prediction of mean pulmonary artery pressure was unsatisfactory (r = 0.65) but improved (r = 0.85) when only patients with a heart rate between 60 and 100 beats/min were considered. The effect of correcting pulmonary flow indexes for heart rate was examined by correlating different flow indexes before and after correction for heart rate. There was a good correlation between corrected acceleration time and either systolic (r = -0.85) or mean (r = -0.83) pulmonary artery pressure. Because of a high incidence of arrhythmia, right ventricular relaxation time could be determined in only 11 patients (22%). Noninvasive prediction of pulmonary artery pressure is feasible in most patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Continuous-wave Doppler echocardiographic detection of pulmonary regurgitation and its application to noninvasive estimation of pulmonary artery pressure

Continuous-wave Doppler echocardiography was used to estimate pulmonary artery pressures by measuring pulmonary regurgitant flow velocity in 21 patients with pulmonary hypertension (mean pulmonary artery pressure greater than or equal to 20 mm Hg) and 24 patients without pulmonary hypertension. The pulmonary regurgitant flow velocity patterns, characterized by a rapid rise in flow velocity immediately after closure of the pulmonary valve and a gradual deceleration until the next pulmonary valve opening, were successfully obtained in 18 of the 21 patients with pulmonary hypertension and in 13 of the 24 patients without pulmonary hypertension. As pulmonary artery pressure increased, pulmonary regurgitant flow velocity became higher; the pulmonary artery-to-right ventricular pressure gradient in diastole (PG) was estimated from the pulmonary regurgitant flow velocity (V) by means of the simplified Bernoulli equation (PG = 4V2). The Doppler-determined pressure gradient at end-diastole correlated well with the catheter measurement of the pressure gradient at end-diastole (r = .94, SEE = 3 mm Hg) and with pulmonary artery end-diastolic pressure (r = .92, SEE = 4 mm Hg). The peak of Doppler-determined pressure gradient during diastole correlated well with mean pulmonary artery pressure (r = .92, SEE = 5 mm Hg). Thus continuous-wave Doppler echocardiography was useful for noninvasive estimation of pulmonary artery pressures.

Noninvasive estimation of right ventricular systolic pressure by Doppler ultrasound in patients with tricuspid regurgitation

We evaluated the accuracy of a noninvasive method for estimating right ventricular systolic pressures in patients with tricuspid regurgitation detected by Doppler ultrasound. Of 62 patients with clinical signs of elevated right-sided pressures, 54 (87%) had jets of tricuspid regurgitation clearly recorded by continuous-wave Doppler ultrasound. By use of the maximum velocity (V) of the regurgitant jet, the systolic pressure gradient (delta P) between right ventricle and right atrium was calculated by the modified Bernoulli equation (delta P = 4V2). Adding the transtricuspid gradient to the mean right atrial pressure (estimated clinically from the jugular veins) gave predictions of right ventricular systolic pressure that correlated well with catheterization values (r = .93, SEE = 8 mm Hg). The tricuspid gradient method provides an accurate and widely applicable method for noninvasive estimation of elevated right ventricular systolic pressures.

The acquired nonprecordial peripheral pulmonary murmur of pulmonary embolism

Two patients had noninvasive and invasive findings consistent with massive pulmonary emboli. Both patients had an acquired nonprecordial peripheral pulmonary murmur on physical examination. One patient also demonstrated a wide, fixed-split second heart sound in addition to the acquired murmur. Both of these physical findings have rarely been reported; however, when present, both the acquired nonprecordial murmur and the widely split second heart sound seem to be associated with extensive and massive pulmonary embolism and, when occurring together, are almost pathognomonic for pulmonary embolism.

The physiologic mechanisms of cardiac and vascular physical signs

Examination of the heart and circulation includes five items: 1) the patient's physical appearance, 2) the arterial pulse, 3) the jugular venous pulse and peripheral veins, 4) the movements of the heart--observation, palpation and percussion of the precordium, and 5) auscultation. This report deals with specific examples that relate cardiac and vascular physical signs to their mechanisms, focusing on each of the five sources. It draws liberally on early accounts, emphasizing that modern investigative techniques often serve chiefly to verify hypotheses posed in the past.

Pulmonary regurgitation in large atrial shunts without pulmonary hypertension

Seven patients with pulmonary regurgitation (PR), normal pulmonary artery (PA) pressures and large left-to-right atrial shunts are reported. Six had secundum atrial septal defects (ASD) and one had anomalous pulmonary venous drainage. These comprised 4% of 180 patients with atrial shunts and normal PA pressures. Pulmonary regurgitation was diagnosed clinically by mid-frequency diastolic decrescendo murmurs beginning after the pulmonic component of the second heart sound, and diagnoses were confirmed by catheterization. In two patients who had serial preoperative catheterizations over 8 and 16 years, PR progressed in one and was present only on the second study in the other. All patients underwent shunt correction, at which time the pulmonic anulus and artery appeared dilated, but the pulmonic valves were normal and did not require revision. In all patients the PR murmur disappeared after shunt correction alone, and on chest X-ray both PA and overall heart size decreased. Although it is known that pulmonary regurgitation occurs with atrial septal defects and pulmonary hypertension, the present study demonstrates that it also occurs with high flow atrial shunts, in which setting it has different implications and is reversible with shunt correction alone.

Acquired continuous murmur associated with acute pulmonary thromboembolism

Two cases of a continuous murmur following an acute pulmonary embolic episode are presented, and eight previously reported cases with an acquired postembolic continuous murmur (found in a review of the literature) are discussed. This finding is present in both chronic and acute pulmonary embolism and is suggestive of significant embolic obstruction. Although the continuous murmur is an unusual sign in patients with pulmonary embolism, its auscultation is often quite distinctive, and its appearance may lead to more definitive diagnostic studies when the presentation or associated clinical findings are nonspecific.

Flow murmur associated with partial occlusion of the right pulmonary artery

An 18-year-old male student presented with a brief history of syncope followed by shortness of breath with exertion, and the development of murmur over the right chest. The symptoms and murmurs were related to a pulmonary embolus which partially occluded the right pulmonary artery and its major branches. The murmur gradually diminished and disappeared when right pulmonary perfusion had almost returned to normal as determined by lung scan. The association of pulmonic flow murmurs and pulmonary emboli is reviewed.

Tricuspid whoop

The present report describes a patient with a whooping murmur secondary to tricuspid insufficiency. The main features of this tricuspid whoop were as follows: variable in time, moving from mid to late systole; unpredictably associated with normal respiratory phases; after deep inspiratory apnea was almost constantly present.

Sound pressure correlates of the second heart sound. An intracardiac sound study

The sound pressure correlates of the second heart sound were studied in 22 patients during diagnostic cardiac catheterization. Simultaneous right ventricular and pulmonary artery pressures were recorded with equisensitive catheter-tip micromanometers together with the external phonocardiogram and ECG. In 12 patients having normal pulmonary vascular resistance (group 1), pulmonic closure sound was coincident with the incisura of the pulmonary artery pressure curve which in turn was separated from the right ventricular pressure trace by an interval denoted hangout. The duration of this interval varied (33-89 msec), was independent of pulmonary artery pressure or resistance and was felt to be primarily a reflection of the capacitance of the pulmonary vascular tree. The absolute value of this interval during inspiration was very similar to the splitting interval and, when subtracted from the Q-P 2 interval, the remaining interval (QRV) was almost identical to the Q-A 2 interval, indicating that the actual duration of right and left ventricular systole is nearly equal. Awareness of the existence of the hangout interval and its hemodynamic determinants offers a reasonable mechanism to explain the audible expiratory splitting of the second heart sound found in patients with idiopathic dilatation of the pulmonary artery following atrial septal defect repair and in one additional patient studied with mild valvular pulmonic stenosis. In nine patients with elevated pulmonary vascular resistance approaching systemic levels (group 2), the absolute value of the hangout interval was markedly reduced (15-28 msec) consistent with the decrease in capacitance of the pulmonary vascular bed and the increased pulmonary vascular resistance known to occur in pulmonary hypertension. In those patients where the duration of right and left ventricular systole were nearly equal, narrow splitting of the second heart sound was present. In those patients where selective prolongation of right ventricular systole occurred, the narrow hangout interval persisted, but the splitting interval was prolonged proportionate to the increased duration of right ventricular systole.