Kinya Matsubara

Diastolic paradoxic jet flow in patients with hypertrophic cardiomyopathy: evidence of concealed apical asynergy with cavity obliteration.

In 20 of 198 patients with hypertrophic cardiomyopathy, Doppler color flow imaging revealed diastolic paradoxic jet flow across the obliterated left ventricular apex toward the base that suggested the presence of a discrete apical chamber. This prospective study characterized echocardiographic, ventriculographic and scintigraphic findings in these patients, as well as their clinical features. Although echocardiography did not directly show the apical chamber in 13 of the 20 patients, left ventriculography always revealed a small apical outpouching separated from the major basal cavity. Systolic bulging of the apex was always followed by early diastolic shrinkage together with persistent cavity narrowing between the two chambers. After the systolic jet flow, the paradoxic jet flow lasted for 366 +/- 160 ms after aortic valve closure and always extended into the diastolic filling period. The maximal velocity of the paradoxic jet flow occurred during isovolumetric relaxation and the mean velocity was 2 +/- 0.8 m/s, indicating a higher diastolic pressure in the apical chamber than in the main ventricle. Compared with patients who manifested cavity obliteration alone, patients with a paradoxic jet flow more often developed systemic embolism (p less than 0.01), ventricular tachycardia (p less than 0.05) and thallium perfusion abnormalities localized to the apical region (p less than 0.01). Thus, paradoxic jet flow could be an important marker of concealed apical asynergy and the risk of adverse clinical events. The higher diastolic apical pressure suggested by the flow may contribute to the development of an apical aneurysm, even in the absence of fixed coronary artery disease.

Sustained cavity obliteration and apical aneurysm formation in apical hypertrophic cardiomyopathy

OBJECTIVES In patients with apical hypertrophic cardiomyopathy (ApHCM), we estimated the severity of cavity obliteration (CO) in the apical potion of the left ventricle and correlated it with various clinical findings including apical aneurysm. BACKGROUND Apical hypertrophic cardiomyopathy sometimes develops apical aneurysm. The apical CO is often exhibited in ApHCM along with apical hypertrophy and ischemia. It remains unclear, however, how the CO and others are related to aneurysm. METHODS In 46 patients with ApHCM, we measured CO time on M-mode echocardiography and corrected it by the R-R interval (cCOT). We divided the 46 patients into the following groups: 17 with cCOT <or=200 ms (no/mild CO group); 18 with cCOT >200 to <or=350 ms (moderate CO group); and 11 with cCOT >350 ms (severe CO group). We then compared apical aneurysm, hypertrophy, ischemia, QT interval, and the like between the three groups. RESULTS The severe CO group exclusively comprised 11 patients having apical aneurysm and paradoxic jet flow. Of the 11 patients, 10 exhibited irreversible defects on exercise single photon emission computed tomography with thallium-201. All with moderate CO showed reversible defects, and none with no/mild CO showed any defects. Left ventricular hypertrophy and the corrected QT interval (QTc) were largest in the severe CO group. There were high correlations between the cCOT, hypertrophy, ischemia, and QTc. Of the 11 patients with severe CO, 6 had nonsustained ventricular tachycardia and 1 had mural thrombus. CONCLUSIONS In ApHCM, sustained CO is an important pathophysiologic condition as well as hypertrophy, ischemia, and prolonged QTc, which are considered jointly related to the development of aneurysm through interactions.

Abnormal course, abnormal flow, and systolic compression of the septal perforator associated with impaired myocardial perfusion in hypertrophic cardiomyopathy

BACKGROUND The septal perforators in hypertrophic cardiomyopathy (HCM) show systolic compression. The compression is thought to be related to the malpositioned septal perforators, but its relation to the development of myocardial ischemia remains controversial. METHODS We examined echocardiographically the blood flow and course of the major septal perforator in 142 consecutive patients with HCM; of these, 94 underwent coronary angiography to assess systolic compression of the septal perforators and 110 had thallium-201 scintigraphy. We then analyzed the relation of the findings in comparison with the results in 15 patients with valvular aortic stenosis (AS). RESULTS The major septal perforator was visualized in 82 patients with HCM and in 8 patients with AS. The visualization did not depend on the pressure gradient between the left ventricle and aorta in the HCM patients, but did in the AS patients. In AS the perforator always showed a normal course near to, and convexly toward, the right ventricle. In 71 of the 82 HCM patients, the perforator was distant from the right-sided endocardium of the ventricular septum and often convex toward the left. The greater the leftward deviation, the higher was the grade of compression. In 48 of the 82 patients with HCM and in all of the 8 patients with AS who showed the flow signal, the septal perforator showed systolic retrograde flow; in the patients with HCM there was a significant correlation (r = 0.54, P <.05) between the peak velocity and the degree of leftward deviation. Furthermore, higher degrees of the leftward deviation and higher degrees of the systolic compression of the major perforator were each associated with a higher incidence of exercise-induced defect of thallium-201. CONCLUSION The echocardiographic, angiographic, and scintigraphic findings in HCM may be closely related to one another. We speculate that the series of abnormalities is initiated by a high intramural pressure and impedance on the septal perforators due to their deviation toward the left.