Angiographic and hemodynamic correlations in hypertrophic cardiomyopathy with intracavitary systolic pressure gradients

Hypertrophic cardiomyopathy. Clinical spectrum and treatment

HCM is a heterogeneous disease genotypically, phenotypically, pathophysiologically, clinically, and therapeutically. In decisions on the management of these patients, it is important to recognize this heterogeneity and to direct therapy at the predominant abnormalities.

Rapid systolic intraventricular velocities after valve replacement for aortic stenosis

To assess the frequency and severity of intraventricular gradients after valve replacement for severe valvular aortic stenosis 25 patients (valve area 0.59 +/- 0.19 cm2) were studied serially with Doppler echocardiography on postoperative days 1, 2, 3, 5 and 7. Pulsed Doppler was used to search for increased intraventricular velocities. Mid-to-late systolic intraventricular velocities > or = 2 m/s were defined as intraventricular gradients. In 13 patients (52%) intraventricular gradients were found at least once during days 1 to 7 (group A) and were most frequent at day 3 (44%). The typical location of these velocities was at the midventricular level close to the septum. In 4 patients intraventricular gradients > 64 mm Hg were found. Left ventricular end-diastolic and end-systolic diameters recorded preoperatively were significantly smaller in group A than in the rest (43.6 +/- 5.4 vs 50 +/- 5.8 mm and 24.6 +/- 5.6 vs 33.1 +/- 7.3 mm, both p < 0.05) and the fractional shortening was significantly higher (44 +/- 9 vs 34 +/- 9%, p < 0.05). It is concluded that intraventricular gradients are frequent during the first week after valve replacement for severe aortic stenosis. These gradients are mostly mild and transient in nature, but significant gradients associated with clinical deterioration may occur. The risk of developing intraventricular gradients postoperatively may be predicted at a preoperative echocardiographic examination, and patients with a small left ventricular cavity size and maintained contractility are at particular risk.(ABSTRACT TRUNCATED AT 250 WORDS)

Increased intensity of the murmur of hypertrophic obstructive cardiomyopathy with carotid sinus pressure

In a prospective study murmurs increased in intensity with carotid sinus pressure in 18 of 26 patients with hypertrophic obstructive cardiomyopathy (HOCM) (sensitivity, 69.2 percent for the 26 patients, 85.7 percent for the 21 patients in whom heart rate and blood pressure decreased with carotid sinus pressure). On the other hand, the murmur remained constant or decreased in all but one of 104 patients with valvular aortic stenosis, mitral insufficiency, hypertrophic nonobstructive cardiomyopathy, and systolic murmurs of miscellaneous origins (specificity, 99 percent; positive predictive value, 94.7 percent). Catheterization, indirect arterial pressure tracings, and echocardiographic studies indicated that carotid sinus pressure-induced bradycardia was associated with increased left ventricular outflow tract obstruction. The carotid sinus pressure-induced increase in the murmur is probably multifactorial: decreased aortic pressure and impedance; increased contractility immediately on sudden slowing of heart rate; further increase in obstruction as the mitral valve systolic anterior movement is enhanced; and delayed vasodilatation maintaining the obstruction even after return of heart rate to precarotid sinus pressure values. An increase in a systolic murmur with carotid sinus pressure is characteristic of HOCM.