Anteroseptal myocardial infarction clinically mimicking right ventricular infarction.

Acute transmural anteroseptal myocardial infarction with acute left ventricular failure can also raise systemic venous pressure in the absence of right ventricular infarction. Right ventricular infarction, therefore, should not be diagnosed simply by the presence of systemic venous congestion.     

Ventricular arrhythmias and left ventricular function: one-year follow-up after myocardial infarction

One hundred and one consecutive post-myocardial infarction (MI) patients were investigated with 24-h long-term ECG registration (LTER), exercise test and radionuclide angiocardiography (RNA) within one month of the MI and after six and 12 months. Patients with low left ventricular ejection fraction (LVEF) or a high value in a quantified phase analysis (Phase SD) were found to have frequent ventricular arrhythmia and high Lown class. Significant correlations between LVEF or phase SD and the number of ventricular arrhythmias or Lown class were found (P less than 0.05). Frequent ventricular arrhythmias and high Lown class were also found in patients with inverse left ventricular wall movement at RNA. Prolonged QTc was found in patients with frequent ventricular arrhythmias. These connections were found at all three investigations during the follow-up year. A significant correlation was not observed between ventricular arrhythmias and exercise capacity, NYHA grouping, ST depression in an exercise test or symptoms of angina pectoris. More than 300 ventricular premature complexes (VPC) per 24 h was found to predict death during the follow-up year as was LVEF less than 30%; complex arrhythmia (i.e., the patient being in Lown classes 3-5) being the only factor to predict repeat-MI during the follow-up year. It is concluded, that ventricular arrhythmias in the post-MI patient reflect the left ventricular performance. Both LVEF and arrhythmias contribute univariately to the risk of death during the first year after an MI. Whether they both carry independent prognostic information for death must be studied in future larger trials.     

Ventricular fibrillation complicating temporary ventricular pacing in acute myocardial infarction: Significance of right ventricular infarction

Five patients with acute myocardial infarction had ventricular fibrillation as a complication of indicated temporary pacing. All five patients had evidence of right ventricular infarction (three patients with postmortem confirmation). The presence of right ventricular infarction seems to be a contributing mechanism involved in the induction of ventricular fibrillation during temporary pacing for bradyarrhythmia complicating acute myocardial infarction.     

Ventricular arrhythmias induced by programmed ventricular stimulation after uncomplicated myocardial infarction.

The aim of this study was to correlate the occurrence of ventricular dysrhythmias induced by programmed ventricular stimulation and sudden cardiac death (SCD) after a first episode of acute myocardial infarction (AMI). Twenty-seven consecutive male patients aged fifty-four +/- six (forty-seven to seventy) years were studied prospectively. Thirty days after AMI, patients were submitted to coronary arteriography and programmed ventricular stimulation with the S2-S3-S4 protocol. Noninvasive assessments, including Holter monitoring, ECG stress test, and radionuclide ejection fraction, were also repeated six and twelve months after AMI. Ventricular dysrhythmias were induced in all patients. According to such response, patients were divided into three groups: (1) repetitive ventricular response (n = 9); (2) nonsustained ventricular tachycardia (n = 8); and (3) sustained ventricular tachycardia (n = 10). All patients consistently developed complex ventricular dysrhythmias at Holter monitoring and ECG stress test. One patient from group 2 suffered SCD and another presented a syncope. Similarly, in group 3, 2 patients suffered SCD, 1 during a documented episode of recurrent AMI. Except for 1 patient, radionuclide ejection fraction remained unchanged throughout the study in all cases. SCD was also unrelated to the presence and type of dysrhythmias at noninvasive evaluation. Therefore, the type of ventricular dysrhythmia induced by the S2-S3-S4 protocol has no correlation with late SCD in patients with a first AMI and preserved ejection fraction.     

The impact of right ventricular infarction on the prevalence of ventricular arrhythmias during acute inferior myocardial infarction

To determine the impact of RV infarction on the prevalence and complexity of ventricular arrhythmias during inferior AMI, 57 patients with no prior MI were studied by 24-hour Holter monitoring on the first and tenth days of AMI. Based on radionuclear studies, patients were allocated into two groups: (1) group A, 21 patients (37 percent) with normal RVEF (greater than or equal to 40 percent); and (2) group B, 36 patients (63 percent) with depressed RVEF (less than 40 percent). There were no significant differences between the groups regarding age and LVEF. Values of RVEF were 47 +/- 6 percent and 31 +/- 6 percent, respectively (p less than 0.05). The RVEF had no influence on the prevalence and complexity of early and late arrhythmias. Stratification of patients in group B into two subgroups based on the extent of RV dysfunction did not reveal any differences in the occurrence of all forms of ectopy (when both groups were matched to group A). Therefore, patients with inferior AMI, with or without RV infarction, have a similar prevalence of arrhythmias. Ventricular ectopic beats may be related to the severity and spread of LV involvement, rather than to RV dysfunction.     

Late potentials and ventricular arrhythmias in arrhythmogenic right ventricular cardiomyopathy

We studied 38 patients (mean age 32 +/- 14 years) with arrhythmogenic right ventricular cardiomyopathy (ARVC) to evaluate the clinical significance of histologic features on endomyocardial biopsy specimens as related to signal-averaged electrocardiography (SAECG), spontaneous ventricular arrhythmias, and hemodynamic features. Fifteen patients presented with ventricular tachycardia or fibrillation (sustained ventricular arrhythmias), 23 with other minor arrhythmias. SAECG variables and right ventricular ejection fraction (RVEF) were statistically correlated with the extent of myocardial fibrosis on biopsy in ARVC. An increased percentage of fibrous tissue (> or = 30%) was a significant univariate predictor of late potentials (p = 0.004) and reduced RVEF (p = 0.02). The 18 patients with late potentials had an increased percentage of fibrous tissue (p = 0.01), a reduced RVEF (p = 0.0004), and a higher risk for sustained ventricular arrhythmias (p = 0.05) than the 20 patients without late potentials. RVEF was the most powerful predictor of late potentials (p = 0.004) at multivariate analysis. Moreover, RVEF < or = 50% was associated with an increased risk for development of sustained ventricular arrhythmias (p = 0.02). A SAECG parameter, namely the root-mean-square voltage of the terminal 40 ms at 25 Hz, was an independent predictive factor for the occurrence of sustained ventricular arrhythmias (p = 0.02). Although fibrous tissue may contribute to delayed myocardial activation in ARVC, a reduced RVEF plays an essential role for spontaneous manifestation of sustained ventricular arrhythmias.     

Cyanotic patient with right ventricular dilatation and ventricular arrhythmias

Uhl's disease is a very rare congenital anomaly of the heart. Extreme dilatation of the right ventricle is accompanied by virtual absence of the right ventricular myocardium. We report on a 30-year-old woman with ventricular arrhythmias and atrial-septal defect where the diagnosis was made by echocardiography and confirmed by angiocardiography. Diagnostic and therapeutic possibilities are discussed.     

Ventricular arrhythmias and left ventricular hypertrophy in essential hypertension

BACKGROUND: Patients with essential hypertension and/or left ventricular hypertrophy and ventricular arrhythmias suffer from an increased mortality rate. In all previous studies on hypertension, the criterion for inclusion was diastolic blood pressure > 95 mmHg. This is a low selective threshold. Our study attempted to evaluate the incidence of ventricular arrhythmia in hypertensive patients not receiving pharmacological treatment and diagnosed by 24-h ambulatory blood pressure monitoring (ABPM), therefore using a more selective criterion than WHO guidelines. METHODS: Hundred-twenty-height consecutive patients with hypertension diagnosed on the basis of WHO guidelines were screened for 24-h ambulatory blood pressure measurement. Eighty-five (66.4%) presented a 24-h mean blood pressure > 135/85 mmHg. All 85 patients were screened for M-mode, B-mode echocardiography, PW Doppler and 24-h ECG Holter recordings. RESULTS: Sixty patients (70.6%) were affected by left ventricular hypertrophy and 25 were free (29.4%). Thirty-six patients (42.4%) had left ventricular diastolic dysfunction, 49 were free (57.6%). According to Lown and Wolf's classification of ventricular arrhythmia, 20 patients (23.5%) presented Grade I arrhythmia, 5 (5.9%) presented Grade II, 4 (4.7%) Grade III, 9 (10.6%) Grade IVA, 20 (23.5%) Grade IVB, 12 (14.1%) Grade V and 15 patients (17.6%) were free from premature ventricular complexes, namely Grade 0 arrhythmia. Left ventricular hypertrophy was found to correlate significantly with the arrhythmia score, r = 0.552 for p < 0.0001. Moreover, left ventricular diastolic dysfunction correlated significantly with the arrhythmia score, r = 0.495 for p < 0.0001. There was also a good correlation between left ventricular hypertrophy and left ventricular diastolic dysfunction, r = 0.616 for p < 0.0001. Among patients affected by left ventricular diastolic dysfunction and left ventricular hypertrophy, the correlation with the arrhythmia score was even closer, r = 0.586 for p < 0.0007. CONCLUSIONS: We conclude that by using a more selective criterion for the diagnosis of hypertension, we can identify patients with a highly significant statistical correlation between left ventricular hypertrophy and ventricular arrhythmia score, and also between diastolic dysfunction and the ventricular arrhythmia score, due to a more severe stage of disease. It is useful to detect those patients affected by ventricular arrhythmias for the primary prevention of major cardiovascular events.     

Isolated right ventricular aneurysm following right ventricular infarction

A 78-year-old man with atherosclerotic heart disease developed extensive right ventricular infarction fibrosis with aneurysm formation following right coronary artery occlusion. No symptoms of right-sided heart failure were present. Postmortem examination revealed that 40% of the right ventricle, 11% of the septum and 7% of the left ventricular free wall were infarcted due to right coronary artery occlusion. This is the first documented case of isolated aneurysm of the right ventricle following infarction and it demonstrates that even extensive right ventricular destruction may be present without symptoms.     

Acute right ventricular infarction

This article reviews the pathophysiology, hemodynamics, natural history, and management of patients with inferior myocardial infarction complicated by right ventricular infarction. Five key areas are highlighted in which advances may impact catheterization and laboratory management of these acutely ill patients.