Noninvasive measurement of left anterior descending coronary artery flow was attempted in 20 normal subjects and 80 patients with cardiovascular disease (valvular heart disease in 34, ischemic heart disease in 26, cardiomyopathy in 15 and other diseases in 5) using combined two-dimensional and Doppler echocardiography. A tubular structure about 2 mm in diameter containing Doppler flow signals was identified in the anterior interventricular sulcus in 7 (35%) of the normal subjects and 40 (50%) of the patients with cardiovascular disease. The blood flow within the tubular structure exhibited a biphasic flow pattern, consisting of systolic and diastolic phases with higher velocity during diastole. The highest velocities were observed in early diastole and, in several cases, a small peak was detected during the atrial contraction phase. On the basis of its spatial orientation and characteristic flow pattern, the tubular structure was identified as the midportion of the left anterior descending coronary artery. In a number of cases it was difficult to detect the systolic blood flow. Although blood flow was normally directed from the cardiac base to the apex, it was reversed toward the base in the patients with a bypass graft to the left anterior descending coronary artery. In patients with severe aortic insufficiency, however, flow velocity was lower during diastole than during systole and the duration of diastolic flow was reduced, failing to continue to the end of diastole. Flow velocity was high in patients with a bypass graft to the left anterior descending coronary artery, aortic stenosis or hypertrophic cardiomyopathy.(ABSTRACT TRUNCATED AT 250 WORDS)
Blood flow in bypass grafts and recipient left anterior descending coronary arteries was evaluated with combined two-dimensional and Doppler echocardiography in 15 patients with an internal mammary artery graft and in 24 patients with a saphenous vein graft. Comparative studies of coronary hemodynamics were also performed regarding these two different grafting techniques. The graft vessel was detected in 11 (79%) of 14 patients with an internal mammary artery graft and in 20 (87%) of 23 with a saphenous vein graft. The recipient left anterior descending coronary artery was detected in 10 (67%) of the former group and 17 (71%) of the latter. The blood flow patterns obtained were generally biphasic, consisting of systolic and diastolic phases with higher velocity during diastole. The maximal diastolic flow velocity in internal mammary artery grafts was much higher than that in saphenous vein grafts. In patients with an internal mammary artery graft, the flow pattern characteristics within the recipient coronary artery were quite similar to those within the arterial graft, and flow velocities within the recipient coronary artery and the arterial graft were quantitatively almost identical. This outcome may contribute to the long-term patency seen in internal mammary artery grafts. On the other hand, the flow velocity in saphenous vein grafts was fairly low throughout the cardiac cycle. Flow velocity in the recipient coronary artery in patients with a saphenous vein graft was accelerated only in early diastole. As a result, the recipient coronary artery flow pattern and velocity differed substantially from those in the saphenous vein graft.(ABSTRACT TRUNCATED AT 250 WORDS)
Doppler echocardiography was used to evaluate the features of interventricular septal rupture in six patients with acute myocardial infarction and to substantiate the hemodynamic data and morphologic findings at surgery or autopsy. Although echocardiographic visualization of the septal rupture was obtained in only two of the six patients, unusual Doppler flow signals were detected in the apical portion of the right ventricle in all six patients. Five patients had unusual flow signals during both systole and diastole; one had such signals only during systole. The location of these unusual flow signals coincided with the site of septal rupture confirmed at surgery or autopsy. The pattern of the flow signals in one cardiac cycle was very similar to that of the pressure difference between the left and right ventricular cavities. These findings indicate that the unusual flow signals represent the left to right shunt flows resulting from septal rupture. In conclusion, Doppler echocardiography may be a very useful tool for diagnosing interventricular septal rupture easily and noninvasively in patients with acute myocardial infarction.
SUMMARYThe Doppler echocardiographic features of coronary arteriovenous fistula were investigated in eight patients with left or right coronary arteriovenous fistulas who had a continuous heart murmur in the upper precordial area and whose diagnoses were confirmed by coronary angiography. In four patients the dilated lumen of the coronary arteriovenous fistula was visualised by cross sectional echocardiography. Of these, three showed abnormal unidirectional continuous flow signals with broad velocity spectra in the fistula. Abnormal, powerful, unidirectional Even with cross sectional echocardiography, however, the site of the shunt-that is, the opening of the fistula-cannot always be detected.In the present study we attempted to identify the coronary arteriovenous fistula, detect the shunt site, and determine the haemodynamic conditions inside the fistula using cross sectional echocardiography and the Doppler technique.Requests for reprints to Dr Kunio Miyatake, National Cardiovascular Center, 125 Fujishiro-dai 5-chome, Suita, Osaka 565, Japan.Accepted for publication 20 December 1983 Patients and methods Eight patients (five men, three women; age range 22-64 years) with a coronary arteriovenous fistula were examined. They were referred to the National Cardiovascular Center for cardiac catheterisation and angiocardiography because of a continuous heart murmur in the upper precordial area, although their exertion capacity was satisfactory. Coronary angiography showed that the continuous heart murmur originated from a coronary arteriovenous fistula. DOPPLER TECHNIQUEThe equipment used included two commercially available cross sectional echocardiographs, a Toshiba SSH 11A/SDS 10A and a SSH 40A/SDS 21A, which incorporated a pulsed Doppler flowmeter in an ultrasonic wide angle phased array system. The ultrasonic frequency used was 2*4 MHz and the pulse repetition rates were 4 and 6 kHz. The sample volume was tear-drop shaped and its size was 4 mm in width 508 on 9 May 2018 by guest. Protected by copyright.
A case of renovascular hypertension is presented with special emphasis on segmental hypoperfusion resulting from single vessel stenosis in the presence of bilateral duplex renal arteries. A forty-year-old male patient presenting with progressive elevation of blood pressure and proteinuria was admitted to our hospital for further evaluation. The elevation of plasma renin activity (PRA) was confirmed only after two-hour standing or under angiotensin converting enzyme inhibition with captopril. PRA obtained from the left renal vein was significantly higher than that from the right renal vein, and the angiogram disclosed bilateral duplex renal arteries and stenosis of 90% or more at the proximal portion in the left upper renal artery. Successful percutaneous transluminal renal angioplasty (PTRA) to the affected single renal artery resulted in normalization of the blood pressure and renin-angiotensin-aldosterone axis. This is the first clinical demonstration of renovascular hypertension resulting from segmental hypoperfusion of a unilateral kidney with lateralizing renal venous renin determination, that was successfully treated by revascularization.( Renovascular hypertension, which accounts for only 0.5% or less of hypertensive patients (1), is the most common curable form of secondary hypertension. Since multiple renal arteries are a relatively common variance and are present in approximately 20% of angiographically studied subjects (2), coexistence of these conditions conceivably may not be uncommon in the hypertensive population. Nonetheless, very few clinical cases of renovascular hypertension resulting from isolated stenosis in multiple renal arteries have been reported. This is probably related to diagnostic difficulties. We herein describe a case of renovascular hypertension resulting from critical stenosis of a single vessel in bilateral multiple renal arteries, which was identified by non-invasive tests and successfully treated by percutaneous transluminal renal angioplasty. Case ReportA forty-year-old male patient was admitted to our hospital presenting progressive hypertension and proteinuria. His blood pressure had been entirely normal until four months before admission, when a blood pressure of 1801100 mmHg and proteinurea were detected at an annual physical check-up. Upon admission, his blood pressure was 210/110 mmHg and heart rate was 48 bpm with normal sinus rhythm. Physical examination disclosed no particular abnormalities, including auscultatory findings of the heart or peripheral arterial pulsations. Funduscopic examination revealed no evidence of hypertensive neuroretinopathy.Neurological examination was essentially negative. Electrocardiogram showed terminal negative T waves in the left precordial leads. Echocardiogram and chest X-ray, however, did not reveal left ventricular hypertrophy or cardiomegaly. Urinalysis was within normal limits except for 2 + proteinuria. The protein content in a 24-h collection of urine was 1.3 g. Major findings in hematology and blood chemistry were within normal ...
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