Related Experiment Videos
[Cineangiographical and histopathological studies on hypertrophic myocardial disease with giant negative T wave
Insights
Patients with giant negative T waves exhibit significant papillary muscle hypertrophy, distinct from other forms of myocardial hypertrophy. This finding suggests a unique pattern of cardiac adaptation in these individuals.
Area of Science:
- Cardiology
- Cardiovascular Physiology
- Medical Imaging
Context:
- Giant negative T waves (GNT) in precordial leads are observed in various cardiac conditions.
- Understanding the underlying myocardial structure associated with GNT is crucial for diagnosis.
- Distinguishing GNT-related hypertrophy from other causes like hypertrophic cardiomyopathy (HCM) and hypertensive heart disease (HHD) is important.
Purpose:
- To investigate the specific characteristics of myocardial hypertrophy in patients presenting with GNT.
- To compare the degree and pattern of hypertrophy in GNT patients with a control group without GNT.
- To evaluate the role of papillary muscle hypertrophy in GNT.
Summary:
- The study examined 19 patients with GNT (HCM, HHD, athletes) and 14 controls. GNT patients showed significantly greater mid-ventricular and apical wall thickness, with a higher apical hypertrophic index.
- Papillary muscle hypertrophy was more severe (Type II) in the GNT group (79%) compared to the non-GNT group (71% Type I).
- Histopathology revealed higher-grade cardiomyocyte hypertrophy in the GNT group, with less prominent disarray and fibrosis, suggesting a distinct hypertrophic pattern.
Impact:
- The findings indicate that papillary muscle hypertrophy is a key feature associated with GNT.
- This specific hypertrophic pattern in GNT patients resembles that seen in mechanically overloaded myocardium.
- The study contributes to understanding secondary heart muscle diseases and refining diagnostic criteria for GNT.
Abstract:
A total of 19 patients consisted of 10 cases with hypertrophic cardiomyopathy (HCM), 6 with hypertensive heart disease (HHD) and 3 with professional bicycle racers with myocardial hypertrophy, showing giant negative T waves greater than 10 mm in precordial leads (GNT-group) was examined by catheterization, cineangiography and endomyocardial biopsy. Fourteen patients of myocardial hypertrophy consisted of 5 cases with HCM, 4 with HHD and 4 with professional bicycle racers without giant negative T (non-GNT-group) were selected as the control. The average of mid-ventricular wall thickness (Tm = 17.4 +/- 4.6 mm) and that of apical wall thickness (Ta = 18.5 +/- 3.6 mm) obtained from the left ventriculogram in GNT group were significantly greater than those in non-GNT group. The average of the apical hypertrophic index (Ta/Tm = 1.1 +/- 0.3) was also greater than that in non-GNT group. For the evaluation of hypertrophy of the papillary muscles, pattern of the hypertrophy was divided into 2 types by the feature of the left ventriculogram in systolic phase of right anterior oblique view, i.e., normal to moderate (type I) and severe (type II). In GNT group, 79% of patients belonged to the type II, whereas 71% of patients in non-GNT group belonged to type I. Histopathologically, the hypertrophy of heart muscle cells in GNT group was higher grade than in non-GNT group. Disarray of the muscle cells and myocardial fibrosis was not so prominent in GNT group. It was concluded that the mode of hypertrophy in GNT group was characterized by the existence of papillary muscle hypertrophy and had similarity to the hypertrophy of known etiologies such as mechanically overloaded myocardium which suggested to the secondary heart muscle diseases.