How sound is the evidence that thrombolysis increases the risk of cardiac rupture?

Effect of microvascular obstruction and intramyocardial hemorrhage by CMR on LV remodeling and outcomes after myocardial infarction: a systematic review and meta-analysis

The goal of this systematic analysis is to provide a comprehensive review of the current cardiac magnetic resonance data on microvascular obstruction (MVO) and intramyocardial hemorrhage (IMH). Data related to the association of MVO and IMH in patients with acute myocardial infarction (MI) with left ventricular (LV) function, volumes, adverse LV remodeling, and major adverse cardiac events (MACE) were critically analyzed. MVO is associated with a lower ejection fraction, increased ventricular volumes and infarct size, and a greater risk of MACE. Late MVO is shown to be a stronger prognostic marker for MACE and cardiac death, recurrent MI, congestive heart failure/heart failure hospitalization, and follow-up LV end-systolic volumes than early MVO. IMH is associated with LV remodeling and MACE on pooled analysis, but because of limited data and heterogeneity in study methodology, the effects of IMH on remodeling require further investigation.

Usefulness of cardiac MRI in the prognosis and follow-up of ischemic heart disease

Cardiac magnetic resonance imaging (MRI) is an important tool that makes it possible to evaluate patients with cardiovascular disease; in addition to infarction and alterations in myocardial perfusion, cardiac MRI is useful for evaluating other phenomena such as microvascular obstruction and ischemia. The main prognostic factors in cardiac MRI are ventricular dysfunction, necrosis in late enhancement sequences, and ischemia in stress sequences. In acute myocardial infarction, cardiac MRI can evaluate the peri-infarct zone and quantify the size of the infarct. Furthermore, cardiac MRI's ability to detect and evaluate microvascular obstruction makes it a fundamental tool for establishing the prognosis of ischemic heart disease. In patients with chronic ischemic heart disease, cardiac MRI can detect ischemia induced by pharmacological stress and can diagnose infarcts that can be missed on other techniques.

CMR of microvascular obstruction and hemorrhage in myocardial infarction

Microvascular obstruction (MO) or no-reflow phenomenon is an established complication of coronary reperfusion therapy for acute myocardial infarction. It is increasingly recognized as a poor prognostic indicator and marker of subsequent adverse LV remodeling. Although MO can be assessed using various imaging modalities including electrocardiography, myocardial contrast echocardiography, nuclear scintigraphy, and coronary angiography, evaluation by cardiovascular magnetic resonance (CMR) is particularly useful in enhancing its detection, diagnosis, and quantification, as well as following its subsequent effects on infarct evolution and healing. MO assessment has become a routine component of the CMR evaluation of acute myocardial infarction and will increasingly play a role in clinical trials of adjunctive reperfusion agents and strategies. This review will summarize the pathophysiology of MO, current CMR approaches to diagnosis, clinical implications, and future directions needed for improving our understanding of this common clinical problem.

Double rupture of interventricular septum and free wall of the left ventricle, as a mechanical complication of acute myocardial infarction: a case report

Introduction

Cardiac ruptures following acute myocardial infarction include rupture of the left ventricle free-wall, ventricular septal defects, and papillary muscle rupture. Double myocardial rupture is a rare complication of acute myocardial infarction (0.3 %) and the report of such cases is exclusively limited to a small series of autopsy studies.

Case presentation

In this report we present the unusual case of a 70-year-old woman with acute anteroseptal myocardial infarction, which was complicated by a combined rupture of the interventricular septum near the apex, and the free wall of the left ventricle with concomitant formation of a pseudoaneurysm. The double myocardial rupture was accidentally discovered 10 days later with echocardiography, when the patient, complaining only of mild exertional dyspnea, was hospitalized for a scheduled coronary angiography. The patient underwent successful surgical correction of the double myocardial rupture along with by-pass grafting.

Conclusion

This report highlights the importance of comprehensive noninvasive predischarge diagnostic evaluation of all postinfarct patients, since serious and potentially life-threatening complications might have not been suspected on clinical grounds.

Effect of thrombolytic therapy on the risk of cardiac rupture and mortality in older patients with first acute myocardial infarction†

AIMS

To evaluate the effect of thrombolysis on mortality and its causes in older patients with acute myocardial infarction (AMI).

METHODS AND RESULTS

An analysis of 706 consecutive patients > or =75 years old with a first AMI enrolled in the PPRIMM75 registry showed that although there were important differences in baseline characteristics among patients treated with thrombolysis, primary angioplasty (PA) and those who did not receive reperfusion therapy, 30 day mortality did not differ (29, 25, and 32%, respectively). The main cause of death in patients treated with thrombolysis was cardiac rupture (54%), whereas most of the other patients died in cardiogenic shock. Patients who received thrombolysis had a higher (P<0.0001) incidence of free wall rupture (FWR) (17.1%) compared with those who did not receive reperfusion therapy (7.9%) or who underwent PA (4.9%). By multivariable analysis, patients treated with thrombolytic therapy (TT) showed an excess risk of FWR (OR, 3.62; 95% CI, 1.79-7.33), a hazard not observed in patients who underwent PA. When compared with patients who did not receive reperfusion therapy, the odds ratio of 30 day mortality was 1.07 (95% CI, 0.65-1.76) for patients treated with thrombolysis and 0.78 (95% CI, 0.45-1.34) for those who underwent PA. The figures for 24 month mortality were 0.78 (95% CI, 0.65-1.76) and 0.67 (95% CI, 0.28-0.81), respectively.

CONCLUSION

Treatment of first AMI with TT increases the risk of FWR in very old patients, a risk not observed in patients treated with PA.

Ventricular rupture during coronary angioplasty for acute reinfarction

Ventricular rupture following acute myocardial infarction usually leads to hemopericardium and death from cardiac tamponade. We describe a patient who had cardiac rupture during direct angioplasty for reinfarction 3 days following an acute anterior myocardial infarction. In this instance, ventricular rupture presented as a severe form of reperfusion injury. The current literature on reperfusion injury and risk factors for cardiac rupture are discussed.

Myocardial rupture after myocardial infarction is related to the perfusion status of the infarct-related coronary artery

Acute or subacute myocardial rupture is a serious and often lethal complication of acute myocardial infarction. The role of an occluded or open culprit coronary artery on the occurrence of this complication is not clear. We therefore reviewed the perfusion status of the infarct-related coronary artery retrospectively in 57 patients who had an initially nonfatal rupture (group A) and 28 patients (including 9 patients from group A) with a postmortem diagnosis of myocardial rupture (group B). In 35 of the 57 patients in group A, a coronary angiogram was available. Complete occlusion or ineffective reperfusion was present in 30 (89%) of 35 patients. The remaining 22 patients of group A showed no clinical signs of reperfusion. All 28 patients of group B had inadequate reperfusion of the infarcted area on postmortem angiography and macroscopic examination of the coronary artery. Our observations suggest that myocardial rupture typically occurs in an infarcted area without reperfusion.

Ventricular septal defects. A case study and discussion

Ventricular septal rupture is a serious complication of acute myocardial infarction (MI) that generally produces progressive circulatory failure and rapid deterioration. Prompt diagnosis followed by surgical repair with peri-operative circulatory support is often life-saving (Mazeika et al 1994). The following is an account of a patient that I cared for, whilst working on the coronary care unit (CCU) as part of an ENB 125 course. The patient was originally admitted with an inferior MI and went on to develop a ventricular septal defect (VSD).

Complicated myocardial infarction

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Indications for fibrinolytic therapy in suspected acute myocardial infarction: collaborative overview of early mortality and major morbidity results from all randomised trials of more than 1000 patients. Fibrinolytic Therapy Trialists' (FTT) Collaborative Group

Large randomised trials have demonstrated that fibrinolytic therapy can reduce mortality in patients with suspected acute myocardial infarction (AMI). The indications for, and contraindications to, this treatment in some categories of patient are disputed, examples being late presentation, elderly patients, and those in cardiogenic shock. This overview aims to help resolve some of the remaining uncertainties. From all trials of fibrinolytic therapy versus control that randomised more than 1000 patients with suspected AMI, information was sought and checked on deaths during the first 5 weeks and on major adverse events occurring during hospitalisation. The nine trials included 58,600 patients, among whom 6177 (10.5%) deaths, 564 (1.0%) strokes, and 436 (0.7%) major non-cerebral bleeds were reported. Fibrinolytic therapy was associated with an excess of deaths during days 0-1 (especially among patients presenting more than 12 h after symptom onset, and in the elderly) but this was outweighed by a much larger benefit during days 2-35. This "early hazard" should not obscure the very clear overall survival advantage that is produced by fibrinolytic therapy. Benefit was observed among patients presenting with ST elevation or bundle-branch block (BBB)--irrespective of age, sex, blood pressure, heart rate, or previous history of myocardial infarction or diabetes--and was greater the earlier treatment began. Among the 45,000 patients presenting with ST elevation or BBB the relation between benefit and delay from symptom onset indicated highly significant absolute mortality reductions of about 30 per 1000 for those presenting within 0-6 h and of about 20 per 1000 for those presenting 7-12 h from onset, and a statistically uncertain benefit of about 10 per 1000 for those presenting at 13-18 h (with more randomised evidence needed in this latter group to assess reliably the net effects of treatment). Fibrinolytic therapy was associated with about 4 extra strokes per 1000 during days 0-1: of these, 2 were associated with early death and so were already accounted for in the overall mortality reduction, 1 was moderately or severely disabling, and 1 was not. This overview indicates that fibrinolytic therapy is beneficial in a much wider range of patients than is currently given such treatment routinely.