Long-term prognostic value of 201Tl single-photon emission computed tomographic myocardial perfusion imaging after coronary stenting

BACKGROUND

The prognostic value of (201)Tl myocardial imaging has been demonstrated in several studies concerning patients with a known significant coronary artery disease. However, the evolution of a coronary stenosis after stenting is difficult to predict. This study was designed to assess the prognostic value of (201)Tl single-photon emission computed tomography (thallium SPECT) perfusion imaging in patients after intracoronary stenting.

METHODS

One hundred fifty-two patients were studied. They were followed up during 40 +/- 13 (mean +/- SD) months after thallium SPECT. Stent-related events were studied after thallium stress testing and included cardiovascular death, myocardial infarction, and revascularization. Stress thallium imaging was performed 5 +/- 2 months after stenting, and ischemia was considered to be present if at least 2 contiguous segments were showing reversible defects.

RESULTS

Only 3 (3%) among the 105 nonischemic patients had major cardiac events during the follow-up versus 13 (28%) of the 47 ischemic patients (P < .001) after thallium SPECT. The relative risk of major cardiac events for patients with significant ischemia was 10.5 compared with nonischemic patients (P < .001). Fourteen (30%) of the ischemic patients and 8 (8%) among the nonischemic patients underwent iterative revascularization (P < .001). Therefore, only 11 (10%) of the nonischemic patients had major cardiac events or revascularization compared with 24 (51%) of the ischemic patients (P < .001).

CONCLUSIONS

Absence of ischemia on thallium SPECT imaging at 5 months after coronary stenting indicates a low risk for cardiovascular events or interventional procedure. These results may have important clinical implications in patient treatment.

[Valvuloplasty of a tricuspid bioprosthesis by the Inoue's technique]

The authors report the case of a patient who had undergone tricuspid valve replacement with a bioprosthesis in 1985 after infectious endocarditis complicated by paradoxical embolism. The appearance of signs of right heart failure eight years later led to the diagnosis of stenotic degeneration of the bioprosthesis. Inoue balloon valvuloplasty was performed with no complications leading to significant improvement in the patient's condition.

[Value of the methylergometrin maleate test in recurrent cardio-circulatory arrests]

A 56-year-old man, with no particular past history, sustained two cardio-circulatory arrests preceded by constrictive chest pain. Coronary arteriography was normal during etiological investigations. The methylergometrine maleate (Méthergin (tm)) test enabled the diagnosis of severe spastic angina and guided appropriate management of this patient.

[What are the indications for digitalis glycosides in the current treatment of cardiac insufficiency?]

Digitalis was discovered over two centuries ago and has been in everyday use for 100 years: however nowadays it is not considered to be the almost exclusive treatment of heart failure as it used to be with diuretic therapy. In the last decade, our understanding of the physiopathology of heart failure and the body's mechanisms of adaptation have improved and this has lead to the use of new molecules and a different approach to the problem of left ventricular failure. The classical contra-indications and precautions of use of digitalis have been studied in detail. The use of digitalis is contested especially in patients in sinus rhythm or with ischemic heart disease and it is used less often in adult cardiac emergencies. The competition between digitalis and vasodilator therapy is now very apparent in some situations; however, the choice between these two groups of drugs (as treatment of first intention or in association) has to be carefully considered in each individual case. The future of digitalis therapy lies without doubt in pediatric cardiology where it remains irreplaceable.

[Transesophageal stimulation in the treatment of atrial flutter and tachysystole. Factor influencing immediate results]

The effectiveness and safety of transoesophageal atrial pacing in the treatment of atrial flutter and tachycardia have been well demonstrated. The purpose of this study was to determine the factors that could influence the results of this method at the end of the procedure. Seventy-seven transoesophageal atrial pacings were performed in 62 unselected consecutive patients with either flutter or atrial tachycardia. The following parameters could be evaluated in 55 patients: date of onset of the arrhythmia, echocardiographic diameter of the left atrium, maximum amplitude of oesophageal atrial potentials, voltage and frequency of stimuli in the last stage of pacing. Our results can be summarized as follows: In both flutter and atrial tachycardia taken globally, conversion to sinus rhythm was obtained in 37 p. 100 of the cases, and conversion to atrial fibrillation in 46.7 p. 100 of the cases. The failure rate was 19.4 p. 100; all failures were due to lack of atrial capture during pacing. The main factor or transoesophageal atrial capture is voltage. Patients must be able to tolerate the voltage needed for capture. In the case of flutter, when capture was achieved a normal-sized left atrium and a high maximum amplitude of oesophageal atrial potentials were factors indicating that conversion to sinus rhythm could be expected. This, however, did not apply to atrial tachycardia. -- Whatever the type of tachyarrhythmia, the more recent its onset the easier its reduction.

[Tolerance and prognostic value of Thallium 201 myocardial tomoscintigraphy with dipyridamole in the aged subject]

The authors present a retrospective study of 46 consecutive patients aged from 70 to 79 years (mean 73.3 +/- 2.5 years) with suspected coronary artery disease who, being unfit for exercise tests, were explored by myocardial scintigraphy with thallium 201 after coronary dilatation with intravenous dipyridamole. The examination was well tolerated by 30 patients. Such classical side-effects as chest pain, malaise, dizziness, headache, flushing, vomiting and transient arrhythmia or repolarization disorders were recorded, but they were not more frequent than in younger subjects. However, the occurrence of severe hypotensive malaise relieved by theophylline in two cases and of angina in about one third of patients with myocardial ischaemia means that the procedure must be performed under close supervision. A fall in blood pressure (-11 mmHg on average) and a rise in heart rate (+8 beats/min on average) were usual. Post-scintigraphy follow-up of patients over a mean period of 11.1 +/- 6.2 months showed that a reversible defect of thallium 201 uptake, due to redistribution, is a highly selective indicator of patients who are particularly exposed to a cardiac accident in the short--or mid-term. Only one out of 26 patients without reversible ischaemia (4 p. 100) subsequently presented with a major coronary event (unstable angina). In contrast, in the group of 20 patients with reversible ischaemia three required early myocardial revascularization; furthermore, five serious accidents (29 p. 100) occurred among the 17 patients who were left under medical treatment, including two sudden deaths, two cases of unstable angina and one case of myocardial infarction.(ABSTRACT TRUNCATED AT 250 WORDS)

[Coronarography in the study of myxoma. Apropos of a case diagnosed by this technic]

In a 59 years old woman presenting a rudimentary picture of myocardial infarction, ventriculograms confirm a limited necrosis and coronarography shows an abnormal vascular image, evoking an intracardiac tumor, while the arteries are free of atherosclerosis or thrombosis on angiography. Although auscultation and echography are normal, the diagnosis of myxoma will be confirmed by angiocardiography, then by surgery and pathology. The advantage of selective coronary angiography in myxomas is considered with 24 cases from the literature having undergone this examination, including 20 cases, among which ours, which present an aspect of "tumoral vascularisation". The particularities of coronarography (aneurysms, embolic obstruction, origin and aspect of hypervascularisation) are analyzed. This technique appears very useful, not only to detect a complication of the tumor or an associated coronaritis, but also to help in the diagnosis of myxomas in cases where angiocardiography or mostly echocardiography are deficient.