[Surgery of mechanical complications of acute myocardial infarct]

Reviewed are the current surgical methods for the treatment of mechanical complications after an acute myocardial infarction, specially the subacute ventricular rupture, the most frequent complication, and in which we have the greatest experience in the world. Mechanical complications constitute the second cause of death after myocardial infarction, following pump failure. The most frequent mechanical complication is ventricular rupture, which is the cause of death in 26% of the cases of acute myocardial infarction. The setting of solid diagnostic tools, with the association of echocardiographic and hemodynamic criteria, has permitted the identification of a large number of patients with subacute ventricular rupture before death, and has allowed them to be treated surgically. The surgical techniques have evolved to more conservative methods and, nowadays, nearly all the patients can be operated on without extracorporeal circulation and using sutureless techniques. The results is greater surgical survival with satisfactory functional status at follow up. The incidence of septal and papillary muscle rupture is considerably less frequent, but of great interest. The surgical results have been improved on the basis of early diagnosis, aggressive surgical attitude, and better reparative and myocardial protection techniques.

Subacute ventricular free-wall rupture presenting as tamponade without frank hemopericardium

Ventricular free-wall rupture is a well-known catastrophic complication of acute myocardial infarction. A significant number of patients present in a subacute fashion and can be successfully treated with surgery if diagnosed promptly. We present a case of subacute free-wall rupture that occurred after an undiagnosed myocardial infarction. The findings at pericardiocentesis were unusual in that the fluid was sanguinous but not frank hemopericardium. This patient represents the first known reported case to present without frank hemopericardium who survived and was successfully treated surgically. The absence of frank hemopericardium should not exclude the diagnosis of free-wall rupture.

[False aneurysm of the left ventricle. A sometimes late finding]

Left ventricular pseudo-aneurysm is a rare complication of myocardial infarction, usually of the inferior wall. It is generally a sudden event due to rupture of the heart which is contained by the pericardium. The outcome is usually rapidly fatal by secondary rupture or adiastole. The authors report a case of pseudo-aneurysm of the left ventricle measuring 3.5 cm in diameter observed following a small inferior wall myocardial infraction in a diabetic patient with a history of inferior wall myocardial infarction 38 years previously. This case is interesting because of the silent character of the pseudo-aneurysm, very probably complicating the previous infarct.

Calcified pseudoaneurysm of the left ventricle

Left ventricular pseudoaneurysm following acute myocardial infarction generally has an extremely poor prognosis without surgical repair. A rare case of long term survival for 23 years following cardiac rupture with subsequent development of a left ventricular pseudoaneurysm after acute myocardial infarction is reported. The patient suffered acute inferoposterior myocardial infarction in July 1974 at the age of 58 years. Clinical course and findings obtained on reassessment in 1992 (transesophageal echocardiography, chest computed tomography and left ventriculography) confirmed a left ventricular pseudoaneurysm. The patient refused surgical resection of the lesion, but remained alive and well in 1997 (81 years old). In this case, it is considered that containment of hemorrhage by pericardial adhesion prevented immediate tamponade and sudden death.

Surgical repair of subacute left ventricular free wall rupture

BACKGROUND

The natural course of subacute ventricular free wall rupture (FWR) as a complication of acute myocardial infarction (MI) is usually lethal. The aim of this study was to investigate the curability of this entity and to report on five patients successfully treated by rapid diagnosis, hemodynamic stabilization, and emergency surgical repair.

METHODS

Five patients with subacute FWR of the left ventricle after previous MI were operated on. Infarctectomy with subsequent closure of the ruptured area was carried out in two patients with anterolateral infarction. Three other patients (two with posterior and one with lateral infarction) were treated by direct closure and the application of a patch. Furthermore, in two patients, concomitant myocardial revascularization was performed.

RESULTS

All patients survived the procedure and were alive and well at long-term follow-up (mean 36.4 months). None of the patients suffered recurrent MI.

CONCLUSIONS

Our experience and a review of the literature shows that prompt diagnosis and emergency surgical intervention may save the patient. Anterior rupture (with a moderate sized infarcted area) is best treated by infarctectomy and subsequent closure of the ventriculotomy with sutures buttressed with felt, whereas posterior rupture may be treated by direct closure and the application of an epicardial patch. Considering our results, we cannot conclude whether additional coronary artery bypass grafting is beneficial or not. Our suggestion is to perform additional myocardial revascularization only if indicated.

[Myocardial rupture after acute myocardial infarct: 2 cases with an unusual clinical presentation]

Myocardial rupture is the second most common reason for in-hospital mortality in patients with acute myocardial infarction, accounting for 8-17% of deaths. The clinical presentation varies due to the possibility of rupture in three main locations: free left ventricular wall (85%), interventricular septum (10%), and papillary muscle (5%). Hypotension, long persisting or repeated chest pain, syncopes, new heart murmurs or weak action should draw attention to the possibility of myocardial rupture, apart from the classical sign of upper inflow congestion. In about 48% of cases immediate surgical intervention can save life. We present two unusual cases of myocardial rupture. Case 1 shows left ventricular free wall rupture with additional rupture of an accessory posterior papillary muscle but without changes in hemodynamic parameters; case 2 involves a rupture of the free left ventricular wall which the patient survived without surgical intervention.

Ischemic left ventricular free wall rupture: prediction, diagnosis, and treatment

Left ventricular free wall rupture is the third leading complication and the second most common cause of death after myocardial infarction. Its occurrence has been considered an unpredictable event usually leading to death. An increased appreciation for the clinical presentation of this syndrome and the nearly ubiquitous use of echocardiography have fostered a rise in the antemortem diagnosis of left ventricular free wall rupture, allowing the possibility of operative repair. Despite the increased reporting of left ventricular free wall rupture, the experience of any one surgeon or surgical group tends to be quite small. We review the current status of rupture prediction, clinical presentation, diagnosis, and treatment options. A recent case of left ventricular free wall rupture referred to the Baylor Cardiothoracic Surgery Group with the misdiagnosis of ruptured dissection of the ascending thoracic aorta is presented to illustrate our approach to this clinical situation.

Diagnostic criteria and management of subacute ventricular free wall rupture complicating acute myocardial infarction

In this prospective study we evaluated the value of the main diagnostic criteria for postinfarction subacute rupture of the ventricular free wall. Two-dimensional echocardiograms and recordings of right atrial pressure and waveform were immediately obtained in every patient exhibiting rapid clinical and/or hemodynamic compromise in the acute infarction setting. The same protocol was applied to patients referred from other hospitals for suspected myocardial rupture. In 28 cases a subacute free wall rupture was identified. In most of the patients the diagnosis was based on the demonstration of hemopericardium and cardiac tamponade by echocardiography, cardiac catheterization and, occasionally, by pericardiocentesis. In 2 instances, the identification of intrapericardial echo densities suggesting clots, in the absence of cardiac tamponade, allowed a diagnosis of subacute rupture. Direct, but indistinct visualization of myocardial rupture was obtained in 4 cases. Among the 28 patients with this complication, 4 died while awaiting surgery and 24 underwent surgical repair (mortality rate 33%). Long-term outcome of survivors was favorable. Various myocardial lesions underlie postinfarction subacute free wall rupture. Clinical presentation varied widely. The diagnosis was based, usually but not always, on the association of hemopericardium and signs of cardiac tamponade. An organized approach to management of this complication of acute myocardial infarction was suggested.

Cardiac rupture complicating cerebral intraarterial thrombolytic therapy

We report a case of fatal cardiac rupture occurring during intraarterial thrombolytic therapy for acute embolic stroke in a patient with recent myocardial infarction.

Perforation of interventricular septum in acute myocardial infarction

Eight cases of ruptured interventricular septum associated with myocardial infarction were diagnosed at Siriraj Hospital between 1985-1995. Clinical congestive heart failure and holosystolic murmur were found in all. Diagnosis was confirmed by echocardiogram and right heart catheterization in all patients. Two patients died from congestive heart failure preoperatively and the third case died from organ failure and sepsis postoperatively. Another five cases underwent successful ventricular septal defect closure and coronary artery bypass with good results.

[Epidemiology of heart wall rupture in myocardial infarct]

In a retrospective study including 1888 consecutive patients (pts) with acute myocardial infarction (AMI) admitted in the years 1989-1993 to the CCU, the relationship between sex, age, history of angina, location of infarction and heart wall rupture has been studied in a multivariate regression model. Female sex (p = 0.0013), older age (p = 0.0001), first angina during the AMI (p = 0.001) were indicative for significantly higher risk of rupture. Women are at higher risk only with anterior wall AMI (p = 0.0393). This risk increases continually with age, more in pts with inferior wall AMI than anterior wall AMI (p = 0.339). Females over the age of 75 with anterior wall AMI and first AP, and males and females over 83 with inferior wall AMI and first AP are at the highest risk of rupture (48.6% of deaths). We conclude that the defined high risk pts should be carefully monitored concerning the signs of impending heart wall rupture.

[Surgical repair of free wall rupture after myocardial infarction]

Between August 1992 and July 1995 five patients with cardiac free wall rupture after acute myocardial infarction underwent surgical treatment in Centro de Cirurgia Torácica do Hospital de S. João. The diagnosis was suggested by the hemodynamic changes and in four patients confirmed with echocardiography and pericardiocentesis. All patients survived and were discharged from the hospital. Medical treatment with inotropic drugs, pericardiocentesis and intraaortic balloon counterpulsation allows hemodynamic stabilization but only early surgery may assure survival.

Postinfarction ventricular free wall rupture: strategies for diagnosis and treatment

Ventricular free wall rupture is a recognized complication of myocardial infarction. In recent years, the widespread availability of echocardiography has enabled prompt antemortem diagnosis. Consequently, an avenue for lifesaving surgical intervention has emerged for this hitherto fatal condition. We review the pathology and discuss strategies for diagnosis, resuscitation, and definitive surgical intervention. We illustrate this review using our experience with a patient whose condition was diagnosed by transthoracic echocardiography and who successfully underwent emergency operation.

Peri-infarct pursestring for repair of subacute cardiac rupture

A 55-year-old woman presented with cardiac tamponade after an inferior myocardial infarction. At surgical exploration there was an extensive area of hematoma associated with cardiac rupture. Rather than infarctectomy and ventricular repair an alternative approach was taken. The patient was successfully managed by the placement of a peri-infarct pursestring together with a superficial stitch closing the exit point of the cardiac rupture.

Subacute cardiac rupture complicating myocardial infarction. A case report

The authors have focused this study on the emergence of subacute ventricular free wall rupture in a seventy-six-year-old patient admitted to hospital for inferior acute myocardial infarction. After six days he showed clinical signs of bradycardia and hypotension evolving to electromechanical dissociation. Given an adequate pharmacologic therapy, the patient was submitted to echocardiography, which was believed to be consistent with myocardial rupture, showing a moderate to large pericardial effusion. Pericardiocentesis of 150 mL of bloody fluid resulted in a further improvement in his hemodynamics. The patient underwent cardiac surgery with repair of the myocardial rupture through a large diaphragmatic infarction by a Dacron polyester fiber graft and pacemaker placement. In conclusion the authors confirm the relevant role of clinical data such as persistent chest pain and hemodynamic instability and the value of echocardiography in identifying subacute myocardial free wall rupture after an episode of acute myocardial infarction.

Concealed post-infarction left ventricular rupture--a diagnostic dilemma

We describe a patient with post-infarction left ventricular rupture exhibiting several atypical features. A successful outcome was achieved after serendipitous surgery.

Pseudoaneurysm of the free wall of the left ventricle without obstruction of major coronary arteries

We report a case of a 63-year-old woman who presented with pseudoaneurysm of the free wall of the left ventricle secondary to myocardial infarction, in the presence of angiographically normal major coronary arteries. This is the only such case we know of, in which the patient underwent successful surgical correction. At last follow-up, the patient was in good condition with no evidence of cardiac disease, at 9 years after surgery.

Pitfalls in the diagnosis and management of papillary muscle rupture: a study of four cases and review of the literature

Four cases of papillary muscle rupture occurring in the setting of acute myocardial infarction are presented, which illustrate the following points: the diagnosis may not be apparent at presentation, a mitral regurgitant murmur may be absent, transesophageal echocardiography may establish the diagnosis when transthoracic echocardiography does not, and appropriate surgical correction can lead to excellent functional recovery.

Relevance of electrocardiographic findings, heart failure, and infarct site in assessing risk and timing of left ventricular free wall rupture during acute myocardial infarction

Clinical and electrocardiographic features of 227 patients who died of an acute myocardial infarction (AMI) were compared with those of 150 survivors of a first AMI. Left ventricular (LV) free wall rupture was found in 93 patients aged > 50 years, but not in 134. The incidence of healed infarct (4 [4%] vs 50 [37%], p < 0.001), heart failure (11 [12%] vs 112 [84%], p < 0.001), and bundle branch block (11 [12%] vs 54 [40%], p < 0.001) was lower in patients with than without LV rupture. In patients with anterior AMI and early rupture (1 day), admission ST elevation was higher than in those with late LV rupture (> 1 day, 6.8 +/- 4.0 vs 4.0 +/- 2.7 mm, p < 0.01). However, lateral wall AMI had minimal ST elevation and accounted for 10% of ruptures. On day 2, the decrease in ST segment in patients with late LV rupture was less than in survivors (0.5 +/- 1.6 vs 3.2 +/- 2.9 mm, p < 0.001). Admission systolic blood pressure in patients who had early rupture was higher than in survivors (155 +/- 22 vs 137 +/- 22 mm Hg, p < 0.001) and in those with late rupture (135 +/- 23 mm Hg, p < 0.001). Late rupture was associated with infarct thinning and triggered by a physical strain in 18 of 45 patients (40%); infarct thinning, however, was present only in 4 of 48 patients (8%) with early rupture (p < 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)