Thomas E. Ratts

Underlying cardiac lesions in adults with infective endocarditis: The changing spectrum

The spectrum of recognized cardiac lesions underlying infective endocarditis has been changing as a result of the decline in incidence of rheumatic heart disease, the recognition of the entity of mitral valve prolapse, and the improvement in cardiac diagnostic techniques. Sixty-three cases of native valve endocarditis diagnosed in Memphis hospitals between 1980 and 1984 were reviewed. All diagnoses of underlying cardiac lesions were confirmed by two-dimensional echocardiography, cardiac catheterization, and/or histopathologic examination of valve tissues. Major categories of underlying lesions were as follows: mitral valve prolapse, 29 percent; no underlying disease, 27 percent; degenerative lesions of the aortic or mitral valve, 21 percent; congenital heart disease, 13 percent; rheumatic heart disease, 6 percent. Thus, mitral valve prolapse and, in the elderly, degenerative lesions have displaced rheumatic and congenital heart diseases as the major conditions underlying endocarditis. Redundancy of the mitral valve leaflets was noted in 17 of 18 patients in whom endocarditis was superimposed upon mitral valve prolapse. The risk of infective endocarditis appears to be substantially increased in the subset of patients with mitral valve prolapse who exhibit valvular redundancy.

The central hemodynamics of severe preeclampsia

Swan-Ganz hemodynamic monitoring in 49 antepartum patients with severe preeclampsia revealed a variable hemodynamic profile. The majority of patients had normal left ventricular filling pressure (8.4 ± 0.2 mm Hg), normal to high cardiac index (4.4 ± 0.1 L · min -1 · m 2 ), and upper normal to moderately elevated systemic vascular resistance (1226 ± 37 dynes · sec · cm -5 ). Eight patients had pulmonary edema and their findings included high wedge pressure (18 ± 1 mm Hg), upper normal to high cardiac index (4.9 ± 0.5 L · min -1 · m 2 ), and normal systemic vascular resistance (964 ± 50 dynes · sec · cm -5 ). Left ventricular function was hyperdynamic in 73% of the 49 patients. Patients with chronic hypertension and superimposed preeclampsia were hemodynamically indistinguishable from patients with preeclampsia alone. We conclude that, in general, preeclampsia is a high cardiac output state associated with an inappropriately high peripheral resistance. The normal wedge and central venous pressures suggest central redistribution of intravascular volume if the generally accepted reports of decreased plasma volume in preeclampsia are correct.

Sodium Sensitivity in Normotensive and Borderline Hypertensive Humans

The responses to sodium depletion and repletion were studied in subgroups of 92 normotensive and 65 borderline hypertensive individuals. The borderline hypertensives were characterized by significantly higher blood pressure, weight, cardiac output, hematocrit and decreased density of conjunctival capillaries and venules. Sodium-sensitivity was defined as an increase in mean arterial blood pressure exceeding 5% during sodium repletion. The prevalence of sodium-sensitivity was higher in blacks than in whites and greater in hypertensives than in normotensives. Sodium-sensitive individuals were characterized by significantly increased forearm vascular resistance and decreased plasma renin activity and aldosterone concentration. The resemblance of these changes to those reported in the Dahl salt-sensitive rat suggests a genetic basis for the response to sodium.

Acquired Left Ventricular to Coronary Sinus Fistula: An Unusual Complication of Acute Myocardial Infarction

Anatomical complications of myocardial infarction include ventricular septal defect and mitral regurgitation. Another unusual complication of myocardial infarction is described, and its diagnosis and surgical management are discussed.

The Central Hemodynamics of Severe Preeclampsia

Swan-Ganz hemodynamic monitoring in 49 antepartum patients with severe preeclampsia revealed a variable hemodynamic profile. The majority of patients had normal left ventricular filling pressure (8.4 +/- 0.2 mm Hg), normal to high cardiac index (4.4 +/- 0.1 L.min-1.m2), and upper normal to moderately elevated systemic vascular resistance (1226 +/- 37 dynes.sec.cm-5). Eight patients had pulmonary edema and their findings included high wedge pressure (18 +/- 1 mm Hg), upper normal to high cardiac index (4.9 +/- 0.5 L.min-1.m2), and normal systemic vascular resistance (964 +/- 50 dynes.sec.cm-5). Left ventricular function was hyperdynamic in 73% of the 49 patients. Patients with chronic hypertension and superimposed preeclampsia were hemodynamically indistinguishable from patients with preeclampsia alone. We conclude that, in general, preeclampsia is a high cardiac output state associated with an inappropriately high peripheral resistance. The normal wedge and central venous pressures suggest central redistribution of intravascular volume if the generally accepted reports of decreased plasma volume in preeclampsia are correct.

Circulatory Congestion in Obese Hypertensive Women: A Subset of Pulmonary Edema in Pregnancy

We describe four obese, chronically hypertensive women presenting with antepartum pulmonary edema in whom invasive hemodynamic monitoring showed elevated wedge pressure, normal to high cardiac index, and normal systemic vascular resistance. Echocardiography revealed large chambers, thick walls, and increased left ventricular mass with normal systolic but abnormal diastolic function. These findings are indicative of intrinsic volume overload occurring in the presence of impaired left ventricular relaxation, a combination resulting in high filling pressures and pulmonary congestion. Diuretic therapy is indicated in this subset of patients, who could not be recognized by the usual clinical parameters such as history and physical examination, chest x-ray, and arterial blood gas.