Pseudo myocardial infarction and pseudo ventricular hypertrophy ECG patterns in Wolff-Parkinson-White syndrome

Diagnostic Challenges: Pseudo-Phenomenon in Wolff-Parkinson-White Syndrome

We reported two patients who presented with non-specific chest symptoms with ECG changes mimicking acute myocardial infarction and ventricular hypertrophy. Both of them were finally confirmed to have Wolff-Parkinson-White (WPW) syndrome after spontaneous resolution of the ECG changes. As a matter of fact, other differential diagnosis should be considered with respect to the ST-segment changes. Diagnostic pitfalls can be avoided by detailed analysis of the ECG before commencement of thrombolytic agents.

Intermittent noninfarction Q waves: a finding suggestive of latent preexcitation

OBJECTIVE

To describe 3 patients who presented with chest pain and intermittent Q waves on the electrocardiogram (ECG) and were subsequently found to have latent preexcitation.

PATIENTS AND METHODS

During a span of 8 years, 3 patients were evaluated because of atypical chest pain and pathologic Q waves in the inferior leads; in all 3 patients, the Q waves were intermittent. No patient had a history of arrhythmia or had Wolff-Parkinson-White pattern on the ECG. Diagnostic and therapeutic interventions for suspected myocardial infarction included cardiac catheterization in 2 patients, intravenous thrombolytic therapy in 1 patient, and heparin in 2 patients. Ischemic heart disease was excluded in all. Patients underwent pharmacological testing and/or electrophysiologic study for suspected preexcitation.

RESULTS

Despite the absence of ECG markers of preexcitation, the presence of a latent accessory atrioventricular connection was confirmed in each patient by pharmacological or electrophysiologic studies.

CONCLUSION

In patients who present with intermittent noninfarction Q waves, the most likely diagnosis is latent preexcitation. Clinicians need to be educated about this clinical diagnosis and encouraged to pursue confirmatory testing. Such patients should be informed about the nature and importance of their electrocardiographic abnormality.

Prominent R wave in lead V1: electrocardiographic differential diagnosis

Tall lead V1 (tall RV1), defined as an R/S ratio equal to or greater than 1, is not an infrequent occurrence in emergency department patients. This electrocardiographic finding exists as a normal variant in only 1% of patients. Physicians should therefore be familiar with the differential diagnosis for this important QRS configuration. The electrocardiographic entities which can present with this finding include right bundle branch block, left ventricular ectopy, right ventricular hypertrophy, acute right ventricular dilation (acute right heart strain), type a Wolff-Parkinson-White syndrome, posterior myocardial infarction, hypertrophic cardiomyopathy, progressive muscular dystrophy, dextrocardia, misplaced precordial leads, and normal variant. Various cases are presented to highlight the different causes of the tall RV1.