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Updated: Jul 17, 2026

Analysis of Coronary Vessels in Cleared Embryonic Hearts
Published on: December 7, 2016
Premature ventricular complex morphology. A marker for left ventricular structure and function
K P Moulton1, T Medcalf, R Lazzara
1Department of Medicine, Oklahoma Medical Center, Oklahoma City 73190.
Insights
The shape of premature ventricular complexes (PVCs) can indicate underlying myocardial disease. Broad notching in PVCs is linked to congestive heart failure and dilated cardiomyopathy, unlike smooth PVCs.
Area of Science:
- Cardiology
- Electrophysiology
- Cardiac Imaging
Background:
- Premature ventricular complexes (PVCs) are common arrhythmias.
- PVC morphology on electrocardiograms (ECGs) may correlate with myocardial disease.
- Understanding this link can aid in diagnosing heart conditions.
Purpose of the Study:
- To investigate the relationship between PVC shape and the presence of myocardial disease.
- To classify PVCs based on QRS complex morphology.
- To identify clinical, ECG, and angiographic differences between PVC morphology groups.
Main Methods:
- 100 patients with PVCs undergoing cardiac catheterization or nuclear angiography were analyzed.
- Patients were divided into two groups based on PVC QRS complex notching: Group 1 (smooth/narrow notching) and Group 2 (broad notching/shelves).
- Clinical data, ECGs, and angiographic variables were compared between groups.
Main Results:
- All patients had heart disease, but no specific etiology differentiated the groups.
- Group 2 showed significantly higher rates of congestive heart failure (66% vs. 12%), dilated cardiomyopathy (38% vs. 2%), and mitral regurgitation (58% vs. 13%) compared to Group 1.
- Group 2 had longer PVC QRS duration (181 ms vs. 134 ms), higher end-diastolic volume index (139 ml/m2 vs. 78 ml/m2), and lower ejection fraction (0.34 vs. 0.59) than Group 1.
Conclusions:
- PVC morphology, specifically broad notching, is associated with significant myocardial disease.
- Broader PVC QRS duration and specific morphological features correlate with reduced ejection fraction and dilated cardiomyopathy.
- PVC shape serves as a valuable, non-invasive indicator for assessing myocardial health.
Abstract:
The shape of a premature ventricular complex (PVC) might reflect the presence or absence of myocardial disease. To test this, 100 patients with a PVC on a 12-lead electrocardiogram at cardiac catheterization or nuclear angiography were classified according to PVC morphology. Group 1 (n = 50) had PVC QRS complexes with either smooth and uninterrupted contour or with narrow (less than 40 msec) notching. Group 2 (n = 50) demonstrated PVC with broad (greater than or equal to 40 msec) notching or shelves. Clinical, electrocardiographic and angiographic variables were assessed to define group differences. All patients had one or more etiological forms of heart disease none of which distinguished either group. Groups 1 and 2 differed with respect to a history of congestive heart failure (12% vs. 66%, p = 0.0004), dilated cardiomyopathy (2% vs. 38%, p = 0.0005), and the presence of mitral regurgitation (13% vs. 58%, p = 0.001), respectively. In group 1, 45 of 50 (90%) patients with a PVC had no notching. Patients in group 2 had greater PVC QRS duration as compared with patients in group 1 (181 +/- 6 vs. 134 +/- 3 msec, p = 0.0001). End-diastolic volume index (EDVI) (78 +/- 3 vs. 139 +/- 11 ml/m2, p = 0.0000) and ejection fraction (EF) (0.59 +/- 0.02 vs. 0.34 +/- 0.03, p = 0.0000) significantly discriminated between group 1 and 2, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
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