David G. Hurrell

Assessment of Right Atrial Pressure With 2-Dimensional and Doppler Echocardiography: A Simultaneous Catheterization and Echocardiographic Study

OBJECTIVE To derive a clinically useful, noninvasive determination of right atrial pressure. Noninvasive assessment of right ventricular systolic pressure from Doppler-derived tricuspid regurgitant velocity requires an accurate assumption of right atrial pressure. PATIENTS AND METHODS Seventy-one patients were studied in the cardiac catheterization laboratory, comparing right atrial pressure (measured at mid systole) with simultaneous 2-dimensional echocardiographic measurement of inferior vena cava diameter and Doppler recordings of hepatic vein systolic, diastolic, and atrial reversal velocities. The initial 28 patients were used to derive a clinical algorithm to predict right atrial pressure, which was tested in the subsequent 43 patients. RESULTS Inferior vena cava dimension correlated directly with right atrial pressure (r2=0.74; P<.001). The systolic filling fraction of the hepatic vein velocity curves correlated poorly with right atrial pressure. However, the correlation between the hepatic vein Doppler sum of systolic forward flow velocity and atrial reversal velocity and right atrial pressure was inverse (r2=0.32; P=.002). With a combination of variables from both inferior vena cava diameter and hepatic vein velocity curves, patients can be divided into those with normal right atrial pressure, mildly increased right atrial pressure, and severely increased right atrial pressure. CONCLUSION The combined information from inferior vena cava diameter and hepatic vein velocity curves can be used to assess right atrial pressure.

Value of Dynamic Respiratory Changes in Left and Right Ventricular Pressures for the Diagnosis of Constrictive Pericarditis

BACKGROUND Conventional cardiac catheterization criteria for the diagnosis of constrictive pericarditis (CP) rely on equalization of intracardiac pressures and have many recognized limitations. Recently, Doppler echocardiographic methods have been used to examine dynamic respiratory changes of increased ventricular interdependence and dissociation of intrathoracic and intracardiac pressures for the diagnosis of CP. These pathophysiological features may be best delineated by cardiac catheterization. Therefore, we studied the accuracy of these dynamic respiratory changes in left ventricular and right ventricular pressure for the diagnosis of CP at cardiac catheterization. METHODS AND RESULTS High-fidelity manometric catheters and respirometry were used to study 36 patients: 15 patients with surgically proven CP (group 1) and 21 patients with other causes of heart failure (group 2). Conventional cardiac catheterization variables used to establish the diagnosis of CP lacked sensitivity and specificity and failed to distinguish between these groups. However, the finding of discordance between right ventricular and left ventricular pressures during inspiration, a sign of increased ventricular interdependence, accurately distinguished patients in group 1 from those in group 2 (P < .05). CONCLUSIONS Examination of dynamic respiratory changes indicating increased ventricular interdependence may be helpful in the diagnosis of CP in the cardiac catheterization laboratory.

Thrombolytic Therapy for Obstruction of Mechanical Prosthetic Valves

This report describes two patients who were treated for obstruction of St. Jude tricuspid valve prostheses. In the patient with the hypereosinophilic syndrome, right heart failure developed 15 days after valve replacement. The other patient had symptoms of right heart failure for 8 weeks; these occurred 15 months after valve implantation. In both patients, thrombolytic therapy was successful and without major sequelae. Herein we review the literature on the use of thrombolysis for obstructed mechanical prosthetic valves and completely summarize the English literature; the efficacy of thrombolysis for obstructed prosthetic valves and the associated morbidity and mortality are emphasized. Recommendations for thrombolysis in clinical practice are provided.

Relation of left ventricular thickness to age and gender in hypertrophic cardiomyopathy

Left ventricular (LV) wall thickening is the most consistent clinical marker of hypertrophic cardiomyopathy (HC), and characteristically increases substantially during adolescence. In this study, we used 2-dimensional echocardiography to develop a cross-sectional profile of LV wall thicknesses in adult patients with HC. We studied a regional community-based cohort of 239 consecutively enrolled patients (aged 18 to 91 years). On average, maximum LV wall thickness decreased relative to increasing age (p = 0.007) within 4 age groups: 22.8 +/- 5.1 mm (18 to 39 years) to 22.1 +/- 5.1 mm (40 to 59 years) to 21.1 +/- 3.7 mm (60 to 74 years) to 20.8 +/- 3.6 mm (>or=75 years). The LV thickness index (summation of wall thicknesses in all 4 segments) also decreased with age (p = 0.017): 63.0 +/- 12.2 mm to 59.8 +/- 11.9 mm to 58.3 +/- 10.4 mm to 57.9 +/- 9.8 mm. Decreasing magnitude of LV hypertrophy was independently associated with increasing age, but not with other relevant disease variables, such as symptoms and outflow obstruction. However, when separated by gender, this inverse relation between age and LV wall thickness was statistically significant only for women (p = 0.007). In conclusion, in an unselected HC cohort, cross-sectional analysis showed a modest but statistically significant inverse relation between age and LV hypertrophy that was largely gender-specific for women. This association constitutes another facet of the natural history of this complex and heterogenous disease and may reflect disproportionate occurrence of premature death in young patients with HC with marked hypertrophy or possibly gradual LV remodeling.

Dual-Chamber Pacing for Cardiomyopathies: A 1996 Clinical Perspective

Implantation of a permanent pacemaker is an accepted mode of therapy for symptomatic bradyarrhythmias. Application of pacemaker technology for the treatment of cardiomyopathies has generated considerable interest and enthusiastic support in recent years. In both hypertrophic cardiomyopathy and dilated cardiomyopathy, dual-chamber pacing has been shown to decrease symptoms and improve hemodynamics; however, not all patients will benefit from dual-chamber pacing. Technical considerations must be acknowledged in order to obtain optimal benefit with dual-chamber pacing. In addition, other more accepted therapies are available for patients with symptomatic cardiomyopathies. The purposes of this article are to review critically the current literature on the use of dual-chamber pacemakers in patients with either hypertrophic or dilated cardiomyopathy and to provide a clinical perspective based on current knowledge.

Pulmonary venous pressure: Relationship to pulmonary artery, pulmonary wedge, and left atrial pressure in normal, lightly sedated dogs

Because pulmonary venous pressure has never been measured, it is unclear whether pulmonary wedge pressure measures left atrial pressure, as commonly assumed, or pressure more upstream in the pulmonary venous or capillary beds. Fluid‐filled mean pulmonary artery and pulmonary wedge pressure were compared with pulmonary venous and left atrial pressure obtained with high‐fidelity micromanometer catheters in eight lightly sedated dogs over a physiologic range of filling pressures. In all conditions, mean pulmonary wedge pressure was virtually identical (r = 0.99) to mean left atrial pressure (slope = 0.99; intercept = −0.46 mm Hg). At the same time, mean pulmonary venous pressure (17.1 ± 6.5 mm Hg) was intermediate between mean pulmonary artery pressure (20.2 ± 6.2 mm Hg) and mean pulmonary wedge pressure (13.3 ± 6.2 mm Hg; P < 0.0001) or mean left atrial pressure (13.4 ± 6.3 mm Hg; P < 0.0001). These relationships were maintained over normal and increased pressure ranges. As measured by conventional flow‐directed pulmonary catheters, mean pulmonary wedge pressure accurately reflects left atrial pressure in lightly sedated, spontaneously breathing normal dogs. Cathet Cardiovasc Intervent 2002;56:432–438.

Echocardiography in the Invasive Laboratory: Utility of Two-Dimensional Echocardiography in Performing Transseptal Catheterization

OBJECTIVE To evaluate the potential utility of transthoracic two-dimensional echocardiography as an aid in the technique of transseptal catheterization. DESIGN We performed a prospective study of 58 patients (29 men and 29 women; mean age, 64.2 years) referred for cardiac catheterization, in whom a systematic approach was used with selective application of two-dimensional echocardiography. MATERIAL AND METHODS The study group of 58 patients had the following diagnoses: mitral stenosis in 17, hypertrophic cardiomyopathy in 13, dilated cardiomyopathy in 13, aortic stenosis in 13, and prosthetic valve dysfunction and pulmonary hypertension in 1 each. With use of only fluoroscopic guidance, initial gentle pressure on the dilator alone was attempted for left atrial access. If the catheter resisted entry into the left atrium, two-dimensional echocardiography was performed to assess the catheters position relative to the atrial septum, and adjustments were made accordingly. Transseptal puncture with a Brockenbrough needle was performed only after confirmation of the catheter position at the region of the fossa ovalis with two-dimensional echocardiography. RESULTS The catheterization procedure was performed without complication in all 58 patients; the mean time to catheter placement was 5.6 +/- 3.5 minutes (range, 3 to 20). Two-dimensional echocardiography was used in 33 patients (57%) when left atrial access was not obtained. On the basis of echocardiographic images, the transseptal catheter had to be repositioned in 16 of these 33 patients (48%). CONCLUSION Two-dimensional echocardiography offers value in demonstrating catheter position during transseptal catheterization and may be used in some patients to ensure transseptal puncture at the region of the fossa ovalis.

Dual-Chamber Pacing in a Patient With Hypertrophic Cardiomyopathy

There is a subset of patients with severely symptomatic hypertrophic obstructive cardiomyopathy who are intolerant of or do not respond to medical therapy. Surgical myectomy has been performed, which provides relief of gradient and improvement of symptoms. Recently, dual-chamber pacing has been proposed as an alternative to surgical myectomy. Dual-chamber pacing can decrease the left ventricular outflow tract gradient, improve symptoms, and perhaps even cause regression of hypertrophy in a subset of patients. This …

Reversible perfusion defects on exercise tomographic thallium imaging in patients with and without collateral flow

A consecutive series of patients underwent exercise thallium imaging and coronary angiography that identified single-vessel right coronary artery disease. Redistribution in the left anterior descending territory was significantly associated with the presence of left-to-right collaterals, whereas collaterals were significantly less frequent in individuals who did not exhibit redistribution.