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To evaluate the clinical significance of reversible perfusion defects that were observed soon after the successful deployment of a coronary stent, 47 patients underwent thallium-201 myocardial scintigraphy and radionuclide angiography in conjunction with adenosine-induced coronary hyperemia before and after complete revascularization. Coronary angiography showed a significant decrease in the percent diameter stenosis (from 87+/-11% before stenting to -1+/-5% after stenting, p

We investigated the presence of subclinical left ventricular dysfunction by determining left ventricular diastolic filling at rest and the left ventricular ejection fraction (LVEF) response to exercise with radionuclide angiography. The subjects were 40 patients with non-insulin-dependent diabetes who showed no evidence of cardiovascular disease based on clinical findings, electrocardiography and 201 Tl perfusion scintigraphy. We also used 123 I-metaiodobenzylguanidine ( 123 I-MIBG) scintigraphy to investigate whether subclinical left ventricular abnormalities were related to adrenergic cardiac dysinnervation. The change in LVEF in response to exercise (ALVEF) was

The objective of this study was to determine noninvasively the likelihood of recovery of the left ventricular ejection fraction (LVEF) in patients with dilated cardiomyopathy (DCM) verified by radionuclide ventriculography. Twenty patients with DCM were classified into two groups according to the LVEF by M-mode echocardiographic findings two years after ventriculographic examination. The LVEF recovered to > or = 50% in 10 patients (Group A), while it was sustained at < 50% in 10 patients (Group B). The clinical features of each group were compared, based on results of physical examination, radionuclide ventriculography, and other diagnostic tests performed on their referral to hospital. Only the systolic blood pressure differed significantly between the two groups, being slightly, but significantly, increased in Group A over that in Group B (P < 0.05). LVEF at rest by radionuclide did not differ (Group A: 31.5 +/- 10.3% vs Group B: 26.5 +/- 9.4%). Peak exercise EF-EF at rest (peak delta EF) in Group A was apparently increased (3.4 +/- 4.0%), while that in Group B was decreased (-4.4 +/- 5.2%). The positive peak delta EF had a highly predictive value of 90% for patients with DCM whose LVEF will recover to more than 50%. The recovery EF-EF at rest did not differ significantly between groups (Group A: 8.4 +/- 4.7 vs Group B: 3.9 +/- 2.3, P < 0.05). Other clinical parameters such as functional class, cardiothoracic ratio, LVEF by echocardiography, cardiac index by Swan-Ganz catheter examination, and histologic examination of biopsied endocardium were indistinguishable in the two groups. The authors conclude that peak delta EF of radionuclide ventriculography on exercise indicates a preservation of LVEF and predicts a good clinical recovery in patients with DCM.

We investigated whether the depressed cardiac response to adrenergic stimulation is accompanied with impaired autonomic function in mildly symptomatic patients with idiopathic dilated cardiomyopathy (DCM). Twenty-seven patients with DCM (New York Heart Association class I or II) and 7 normal control subjects underwent exercise radionuclide ventriculography and 24-h ambulatory ECG. The following frequency components of heart rate variability were calculated: the areas under the low (low frequency component [LF], 0.04 to 0.15 Hz), high (high frequency component [HF], 0.15 to 0.40 Hz), and total frequency portions of the spectrum. HF and HF% (the ratio of HF to total power) were calculated as indexes of specific vagal influences, and LF% (the ratio of LF to total power) and the ratio of LF to HF were of sympathetic tone. The left ventricular ejection fraction (LVEF) increased by more than 5% in all normal control subjects during exercise, whereas 17 (63%) of patients failed to show more than a 5% increase in LVEF. The profile of the mean hourly HF% and LF/HF showed circadian variations in normal control subjects but not in patients. The HF and HF% during sleep were significantly lower and the LF/HF during sleep was higher in patients than in normal control subjects. In patients, the LVEF during exercise minus LVEF at rest was significantly correlated with HF, LF%, and LF/HF during sleep, and with the ratios of the mean values during early morning to the mean daytime values for those spectral indexes. Our results demonstrated that mildly symptomatic patients with DCM showed an attenuated cardiac response to exercise and altered autonomic function, and their close relationship, suggesting that autonomic nervous activity contributes to cardiac desensitization in DCM.

To clarify how angiotensin converting enzyme inhibition affects left ventricular function through ventricular unloading, ventricular wall stress, ventricular volumes, and other cardiac indices and exercise tolerance were evaluated in 17 patients with mild to moderate chronic congestive heart failure before and after 3 months of treatment with enalapril. Echocardiographic examination revealed that treatment with this angiotensin converting enzyme inhibitor resulted in significant reductions in end-systolic wall stress (117 +/- 25 to 89 +/- 28 g/cm2, p < 0.01) and left ventricular volume indices (end-diastolic: 163 +/- 56 to 143 +/- 60; end-systolic 99 +/- 51 to 77 +/- 57 ml/m2 p < 0.01). Ejection fraction (42 +/- 11 to 48 +/- 13%, p < 0.01) and systolic blood pressure/end-systolic volume (SBP/ESV; 1.06 +/- 0.30 to 1.33 +/- 0.48 mmHg/ml, p < 0.01) were both increased. By radionuclide ventriculography, ejection fraction and peak ejection rate (2.30 +/- 0.74 to 2.80 +/- 0.76 EDV/sec, p < 0.01) were increased, while time to peak ejection, time to peak filling, and peak filling rate were unchanged. Heart rate and double product at exercise were decreased and delta EF was significantly increased (-1.4 +/- 4.1 to 1.6 +/- 4.4%, p < 0.02). The decrease in end-systolic wall stress was consistently related to both the increase in ejection fraction and SBP/ESV, while the decrease in end-diastolic volume was related only to SBP/ESV and not to ejection fraction. Furthermore, there was a direct relationship between the decrease in systolic wall stress and the decrease in end-diastolic volume.(ABSTRACT TRUNCATED AT 250 WORDS)

The diagnostic values of adenosine, dobutamine, and exercise radionuclide ventriculography (RNVG) in the detection of coronary artery disease (CAD), and the characteristics of those patients who showed myocardial ischemia during the infusion of adenosine or dobutamine were assessed in 41 patients with suspected CAD. Sensitivity, specificity, and accuracy, respectively, for detecting patients with CAD were 35 (p < 0.01 vs. exercise RNVG), 100 and 46% (p < 0.01 vs. exercise RNVG) with adenosine RNVG, 74, 100 and 78% with dobutamine RNVG and 88, 71 and 85% with exercise RNVG. There was a significant difference in physiologic parameters during the provocation of ischemia by adenosine versus exercise RNVG, although these parameters were similar by dobutamine and exercise RNVG. Stepwise discriminant analysis revealed that the number of stenotic vessels was an important and independent predictor for the myocardial ischemia induced by each stress; the peak filling rate was the only predictor for adenosine-induced ischemia. Dobutamine induced myocardial ischemia in a way similar to that of exercise, and was more useful than adenosine for pharmacologic stress RNVG. The mechanism of the adenosine-induced ischemia seemed to differ from that of the ischemia induced by dobutamine or exercise, and to be closely associated with left ventricular diastolic function.

A newly developed blood pool agent 99mTc-DTPA-HSA (Japan Mediphysics, Inc.) was used for ECG gated blood pool scintigraphy. The radiopharmaceutical remained in the blood pool with disappearance half time of 420 min in a healthy subject. The gated blood pool study in the same subject clearly demonstrated contracting left ventricle and right ventricle both with planar and SPECT images. Three healthy volunteers and 14 patients were included in the study, in that gated blood pool images were successfully obtained. The left ventricular ejection fraction (LVEF) calculated by the analysis of LV volume curves correlated well with those obtained by echocardiography (US). In 11 patients with implanted pacemaker for complete atrioventricular block and sick sinus syndrome changes of LVEF were evaluated in relation to pacing rates. The mean LVEF at pacing rate of 60/min was 58.5%, which decreased to 54.4% at 100/min pacing rate. However, changes of LVEF in individual patient did not show same pattern. We conclude that 99mTc-DTPA-HSA is a convenient blood pool scanning agent which does not require time consuming labeling preparations. Stable labeling and slow blood clearance allows its use for repeat measurements of LVEF in different conditions in a patient such as with pacemaker.

Radionuclide angiographic measurements of left ventricular ejection fraction were performed at rest and during exercise in 10 normal persons and 11 patients with coronary artery disease. Exercise was continued on a supine bicycle exercise table up to a symptom-limited maximum. Plasma levels of atrial natriuretic peptide (ANP) were also determined at rest and during exercise. Ejection fraction in the normal volunteers was 59 +/- 3% (mean +/- SEM) at rest and increased significantly (p less than 0.01) to 69 +/- 3% during exercise. Ejection fraction in the patients was 47 +/- 5% at rest and did not change significantly during exercise (51 +/- 7%). Plasma ANP in the normals rose significantly (p less than 0.01) from 62 +/- 16 pg/ml at rest to 454 +/- 94 pg/ml during exercise. Plasma ANP in the patients also rose significantly (p less than 0.01) from 231 +/- 102 pg/ml to 794 +/- 170 pg/ml. The response of plasma ANP to exercise was enhanced significantly (p less than 0.05) in the patients as compared with the normals in relation to ejection fraction by analysis of covariance. In both the normals and the patients, plasma ANP was inversely and significantly correlated with ejection fraction during exercise (r = -0.46, p less than 0.05, n = 21), however, not at rest. Because it has been reported that plasma ANP is correlated positively with pulmonary artery wedge pressure, the estimation of plasma ANP during an exercise stress test might be used for the evaluation of cardiac reserve in coronary artery disease.

心房細動,脳塞栓を合併した,本邦における最高令の三心房心の1例を報告する.症例は54才の男性で, 34才頃より労作時呼吸困難を自覚, 43才時心拡大と心房細動より僧帽弁狭窄症を疑われ精査を受けたが,原因は不明であつた. 51才時突然の意識消失,左半身不完全麻痺にて脳塞栓と診断された.昭和56年2月,労作時呼吸困難増悪のため入院.心尖部に拡張期雑音が聴取され,胸部X線像では心胸郭比59%で,左第3弓の直線化および右第2弓の突出を認めた.心電図は心房細動で,平均電気軸は-20°, V1誘導でrSR′パターンを認めた.断層心エコーにて左房内に異常隔壁エコーを認め,僧帽弁には異常は見られなかつた.左房造影像でも同様に左房内隔壁を認め,肺静脈はすべて隔壁上部のaccessory chamberに流入していた.又,心内短絡の合併は認めなかつた.以上よりclassic cor triatriatumと診断し,左房内隔壁切除が行なわれた.隔壁には大きさ約1cm2の交通孔が左心耳直上に認められた.これまでの本邦報告37例のうち,本症例は最高令であり,又脳塞栓合併の報告は他に見られていない.