Technetium-99m-sestamibi SPECT to detect restenosis after successful percutaneous coronary angioplasty.

Unlabelled: This study evaluated the accuracy of 99mTc SPECT in predicting restenosis after primary successful PTCA.

Methods: Thirty-seven patients with equivocal symptom-limited exercise stress testing were evaluated. All patients underwent separate day exercise-rest 99mTc-sestamibi SPECT.

Prognostic value of tomographic rest-redistribution thallium 201 imaging in medically treated patients with coronary artery disease and left ventricular dysfunction.

Background: Previous studies show that rest-redistribution thallium imaging is useful in the assessment of myocardial viability. The impact of such studies on patient outcome is not well defined. This study examined the prognostic value of tomographic rest-redistribution 201T1 imaging in 81 medically treated patients with coronary artery disease and left ventricular dysfunction.

Comparison of nuclear cardiology in the United States and Europe.

Nuclear Cardiology is widely available and a widely accepted tool for diagnosis and management of coronary artery disease both in the US and in Europe. Although the most common indications for nuclear studies are similar in the US and Europe, different social and economical environments may affect the practice of Nuclear Cardiology. The aim of this paper is to identify key issues and to provide some information on the similarities and differences which characterize the practice of Nuclear Cardiology in the US and Europe.

Evaluation of technetium-99m-sestamibi lung uptake: correlation with left ventricular function.

Unlabelled: Lung uptake of 201Tl is a reliable marker of left ventricular dysfunction. The goal of our study was to establish whether the evaluation of lung-to-heart uptake ratios (LHR) with 99mTc-sestamibi imaging may provide valuable information.

Methods: We studied 72 male subjects with recent anterior myocardial infarction undergoing 99mTc-sestamibi first-pass ventriculography and SPECT perfusion imaging.

Effects of short- and long-term carvedilol administration on rest and exercise hemodynamic variables, exercise capacity and clinical conditions in patients with idiopathic dilated cardiomyopathy.

Objectives: The study evaluated the effects of short- and long-term administration of carvedilol in patients with idiopathic dilated cardiomyopathy.

Background: Carvedilol is a beta-adrenergic blocking agent with vasodilator activity that might be well tolerated in patients with heart failure.

Methods: Forty patients with idiopathic dilated cardiomyopathy treated with digoxin, furosemide and angiotensin-converting enzyme inhibitors were randomized in a double-blind manner to receive either placebo or carvedilol.

Spontaneous delayed recovery of perfusion and contraction after the first 5 weeks after anterior infarction. Evidence for the presence of hibernating myocardium in the infarcted area.

Background: In patients with ventricular dysfunction caused by stunning or hibernation, it is not clear when complete recovery of the salvaged myocardium occurs after acute myocardial infarction. The purpose of this study was to determine whether a delayed recovery of perfusion and contraction continues even after the subacute phase.

Methods And Results: We prospectively studied 71 consecutive male patients with first uncomplicated Q-wave anterior infarction.

Maldistribution of regional myocardial perfusion at rest in patients with coronary artery disease and no previous myocardial infarction, evidenced by 99mTc-Sestamibi scintigraphy.

Since myocardial 99mTc-Sestamibi uptake is closely related to coronary blood flow and the tracer does not redistribute, resting perfusion defects may be observed even in viable regions supplied by vessels with severe stenosis. The incidence and the clinical significance of 99mTc-Sestamibi uptake defects at rest were investigated in 60 men with suspected coronary artery disease and no previous myocardial infarction, in a multicenter study. Of 60 patients, 12 showed normal coronary arteries and 48 significant coronary artery disease (> 50% luminal narrowing).

Left ventricular dysfunction due to stunning and hibernation in patients.

Left ventricular dysfunction is in most cases the consequence of myocardial ischemia. It may occur transiently during an attack of angina and usually it is reversible. It may persist over hours or even days in patients after an episode of ischemia followed by reperfusion, leading to the so-called condition of stunning.

Echocardiography during infusion of dobutamine for identification of reversibly dysfunction in patients with chronic coronary artery disease.

Objectives: The aim of this study was to test whether the contractile response of akinetic myocardium to low dose dobutamine is useful for detecting myocardial viability in patients with coronary artery disease and persistent left ventricular dysfunction.

Background: In some patients with chronic coronary artery disease, persistent abnormalities of left ventricular wall motion can be reversed by successful coronary artery bypass surgery. Thus, identification of potentially reversible dysfunction has important therapeutic and prognostic implications.

[Stress and ischemic heart disease].

The role of mental stress in ischemic heart disease is two-fold: as a risk factor of coronary artery disease and as a trigger of acute ischemic attacks in patients with established coronary atherosclerosis. The role of stress as a risk factor is still controversial. Data regarding the relationship between occupational factors and development of coronary atherosclerosis have not been confirmed.

Recovery of myocardial function. The ultimate target of coronary revascularization.

Recovery of myocardial contraction represents an important target of coronary revascularization and the preoperative recognition of viable akinetic (hibernating) myocardium is a crucial point of the preoperative investigation of patients with chronically depressed left ventricular function. In 14 patients dobutamine infusion during echocardiography was utilized to evoke the contractile reserve retained by viable akinetic segments. Redistribution of thallium(TI)-201 after the rest injection was also used to assess the viability of akinetic areas.

Assessment of myocardial perfusion with thallium-201 scintigraphy in exercise-induced left bundle branch block: diagnostic value and clinical significance.

Myocardial perfusion scintigraphy with thallium-201 was performed in 33 subjects (mean age 45 years, range 28-61) with exercise-induced, rate-dependent left bundle branch block (LBBB) in order to assess both the value of Thallium-201 myocardial imaging for the diagnosis of coronary artery disease (CAD) and the pathogenesis (ischaemic or not) of the conduction defect. Of the 33 patients evaluated, 16 had chest pain suggestive of CAD and 17 were asymptomatic. None had a history of prior myocardial infarction or clinical and echocardiographic signs of heart disease.

Coronary revascularization and recovery of function: the ultimate target.

Recovery of contraction in the akinetic segments represents an important target of coronary revascularization, and the preoperative recognition of viable dyssynergic (hibernating) myocardium is a crucial point in the preoperative investigation of patients with chronically depressed left ventricular function. Dobutamine-echocardiography was utilized in 14 patients to study the contractile reserve retained by viable segments. Redistribution of thallium-201 after rest injection was also used to assess the viability of these areas.

Hibernating myocardium in patients with coronary artery disease: identification and clinical importance.

The term hibernating myocardium describes a particular outcome of myocardial ischemia in which myocytes show a chronically depressed contractile ability but remain viable. Revascularization of hibernating tissue causes a recovery of mechanical function that correlates with long-term survival. Therefore it is important clinically to distinguish hibernating from infarcted myocardium, since asynergies due to hibernation will improve on reperfusion, whilst those due to infarct will not.

Stunned and hibernating myocardium: possibility of intervention.

There are several potential outcomes of myocardial ischemia. When ischemia is severe and prolonged, irreversible damage occurs and there is no recovery of contractile function. When myocardial ischemia is less severe but still prolonged, myocytes may remain viable but exhibit depressed contractile function.

Transient prolonged postischemic ventricular dilatation documented by 99mTc MIBI scan.

We describe two cases of prolonged postischemic ventricular dilatation during myocardial scintigraphy with 99mTc MIBI, the new perfusion tracer that has only negligible redistribution. Ventricular dilatation, caused by true chamber dilatation and/or subendocardial ischemia, was still present over two hours after the induced ischemic episode, suggesting a prolonged duration of such a commonly believed fleeting scintigraphic finding.

Electrocardiographic markers of ischemia during mental stress testing in postinfarction patients. Role of body surface mapping.

In patients with coronary artery disease, radionuclide investigations have documented a high incidence of mental stress-induced myocardial ischemia in the absence of significant electrocardiographic changes and/or angina. To investigate the causes of the low electrocardiographic sensitivity, we recorded body surface maps during mental arithmetic in 22 normal volunteers and 37 postinfarction patients with residual exercise ischemia. Myocardial perfusion was studied with thallium-201 or technetium-99 (SESTAMIBI) planar scans.

Effects of mental stress on myocardial perfusion in patients with ischemic heart disease.

The purpose of the present study was to determine whether and to what extent mental stress can reproduce the perfusion defects that are known to be induced by exercise. Twenty-four patients with recent myocardial infarction (New York Heart Association functional class I) and evidence of ischemic response were evaluated by means of SESTAMIBI scintigraphy performed once after exercise and then again within 2 days after mental arithmetic. Baseline, exercise, and mental stress planar scintigrams were divided into 15 segments, and each segment was reviewed and scored on a scale of 0 to 3 by experienced observers using circumferential profile analysis.