[Left ventricular aneurysm with normal coronary arteriogram after myocardial infarction].

Left ventricular aneurysms after myocardial infarction are generally considered one of the complications of severe coronary artery disease. Postinfarction ventricular aneurysms with normal coronary arteriogram are rare. Only a few cases have been reported previously in Japan. We examined the incidence and the clinical characteristics of postinfarction ventricular aneurysms without coronary obstruction. Among the consecutive 1800 patients studied in our laboratory with selective coronary cineangiography and left ventriography, we found 5 (4 male, 1 female) patients with left ventricular aneurysms with no or minimal coronary arterial obstruction. The patient's ages ranged from 34 to 83 with a mean of 59. Interestingly, no patient had prior anginal history, and every case occurred with a first sudden attack of chest pain. The likely mechanisms causing the development of myocardial infarction were coronary spasm and/or thromboembolic accident. One patient, in whom a coronary induction test was performed, showed positive findings. It is possible that poor collateral circulation and well preserved contraction of viable myocardium in these patients bring about the formation of left ventricular aneurysm after myocardial infarction with normal coronary arteriogram.

[Electrocardiographic ST-segment deviation in acute inferoposterior myocardial infarction caused by obstruction of the left circumflex coronary artery].

Electrocardiographic ST-segment deviation was evaluated as a method for identifying the occlusive site of the coronary artery in acute inferoposterior myocardial infarction. ST-segment elevation in 2 or more of the inferior leads (II, III, aVF) occurred in 11 of 22 patients (50%) with left circumflex coronary artery occlusion, and in 24 of 27 patients (88.9%) with right coronary artery occlusion. The ST-segment elevation in the inferior leads was 3.8 +/- 2.6 mm (mean +/- SD) in left circumflex coronary artery occlusion and 8.5 +/- 4.9 mm in right coronary artery occlusion (p < 0.01). Two millimeters or greater ST-segment elevation in any 2 or more of the inferior leads was observed in 81.5% of the patients with right coronary artery occlusion, but in only 13.6% of the patients with left circumflex coronary artery occlusion (p < 0.01). ST-segment elevation in the inferior leads was found in 8 of 10 patients (80%) with distal left circumflex coronary artery (segment 13) occlusion, but in only 2 of 9 patients (22.2%) with proximal left circumflex coronary artery (segment 11) occlusion (p < 0.05). These findings suggest that identification of the site of coronary artery occlusion, left circumflex coronary artery or right coronary artery, in patients with acute inferoposterior myocardial infarction can be indicated by the location, summation and intensity of the ST-segment elevation in the inferior leads.(ABSTRACT TRUNCATED AT 250 WORDS)

[Partial rupture progressing to complete rupture of the left ventricular anterior papillary muscle after acute myocardial infarction: a case report].

A 71-year old man presented with partial rupture progressing to complete rupture of the left ventricular anterior papillary muscle after acute anterolateral myocardial infarction. The progressive rupture was demonstrated by transthoracic and transesophageal echocardiography. Transthoracic echocardiography showed exaggerated systolic prolapse of the anterior mitral leaflet with grade III mitral regurgitation and partial disruption of the anterolateral papillary muscle, but transesophageal echocardiography during surgery disclosed the progression of the partial rupture to complete rupture. The flail anterior mitral leaflet with severe mitral regurgitation and the head of the ruptured papillary muscle into the left atrium in systole were confirmed. The patient was treated by coronary artery bypass grafting and mitral valve prosthesis using a St. Jude Medical valve with good outcome.

[Left atrial function and left atrial appendage flow velocity in hypertrophic cardiomyopathy: comparison of patients with and without paroxysmal atrial fibrillation].

The involvement of left atrial (LA) appendage flow velocity in reduced left atrial function was investigated in 24 patients with hypertrophic cardiomyopathy, who retained sinus rhythm at the examination. Patients were divided into 11 with a history of paroxysmal atrial fibrillation [PAf(+)] and 13 without such history [PAf(-)]. Transthoracic echocardiography was performed to evaluate LA fractional shortening (LA%FS) and mean velocity of circumferential LA fiber shortening (LAmVcf), as contractile functions of the left atrium at the phase of active atrial contraction. Transesophageal echocardiographic Doppler examination was performed in all patients to measure the LA appendage velocity. In all patients, significant positive correlations were observed between the LA appendage velocity and LA%FS (r = 0.50, p < 0.05) or LAmVcf (r = 0.82, p < 0.001). LAmVcf and LA appendage velocity in patients with paroxysmal fibrillation were significantly lower than in those without (0.84 +/- 0.15 vs 1.28 +/- 0.37 circ/sec, 44 +/- 12 vs 65 +/- 20 cm/sec, both p < 0.01), whereas LA diameter was greater in the former compared to the latter (45 +/- 5 vs 38 +/- 5 mm, p < 0.01). LAmVcf and LA appendage velocity were low in four patients with cerebral infarction or transient cerebral ischemic attack (LAmVcf < 1.0 circ/sec, LA appendage velocity < or = 40 cm/sec). Importantly, all these patients had a history of paroxysmal fibrillation. These results indicate that there is a close relationship between LA appendage velocity and LA contractile function in patients with hypertrophic cardiomyopathy with paroxysmal atrial fibrilation, and these patients have potential risk of cerebral infarction.