Right coronary artery ectasia with coronary arteriovenous fistula mimicking Takotsubo-like left ventricular dysfunction in the electrocardiogram

Right ventricular (RV) dysfunction can lead to complications after acute inferior myocardial infarction (MI). However, it is unclear how RV failure after MI contributes to left-sided dysfunction. The aim of the present study was to investigate the consequences of right coronary artery (RCA) ligation in mice. RCA ligation was performed in C57BL/6JRj mice ( n = 38). The cardiac phenotypes were characterized using high-resolution echocardiography performed up to 4 wk post-RCA ligation. Infarct size was measured using 2,3,5-triphenyltetrazolium chloride staining 24 h post-RCA ligation, and the extent of the fibrotic area was determined 4 wk after MI. RV dysfunction was confirmed 24 h post-RCA ligation by a decrease in the tricuspid annular plane systolic excursion ( P < 0.001) and RV longitudinal strain analysis ( P < 0.001). Infarct size measured ex vivo represented 45.1 ± 9.1% of the RV free wall. RCA permanent ligation increased the RV-to-left ventricular (LV) area ratio ( P < 0.01). Septum hypertrophy ( P < 0.01) was associated with diastolic septal flattening. During the 4-wk post-RCA ligation, LV ejection fraction was preserved, yet it was associated with impaired LV diastolic parameters ( E/ E′, global strain rate during early diastole). Histological staining after 4 wk confirmed the remodeling process with a thin and fibrotic RV. This study validates that RCA ligation in mice is feasible and induces RV heart failure associated with the development of LV diastolic dysfunction. Our model offers a new opportunity to study mechanisms and treatments of RV/LV dysfunction after MI. NEW & NOTEWORTHY Right ventricular (RV) dysfunction frequently causes complications after acute inferior myocardial infarction. How RV failure contributes to left-sided dysfunction is elusive because of the lack of models to study molecular mechanisms. Here, we created a new model of myocardial infarction by permanently tying the right coronary artery in mice. This model offers a new opportunity to unravel mechanisms underlying RV/left ventricular dysfunction and evaluate drug therapy.

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Impact of Renin-Angiotensin-Aldosterone System Gene Polymorphisms on Left Ventricular Dysfunction in Coronary Artery Disease Patients

Disease Markers ◽

10.1155/2012/854150 ◽

2012 ◽

Vol 32 (1) ◽

pp. 33-41 ◽

Cited By ~ 13

Author(s):

Avshesh Mishra ◽

Anshika Srivastava ◽

T. Mittal ◽

N. Garg ◽

B. Mittal

Keyword(s):

Coronary Artery Disease ◽

Cardiac Output ◽

Coronary Artery ◽

Left Ventricular Dysfunction ◽

Ventricular Dysfunction ◽

Left Ventricular ◽

P Value ◽

Renin Angiotensin Aldosterone System ◽

Renin Angiotensin ◽

Artery Disease

Background: Left ventricular dysfunction (LVD), followed by fall in cardiac output is one of the major complications in some coronary artery disease (CAD) patients. The decreased cardiac output over time leads to activation of the renin-angiotensin-aldosterone system which results in vasoconstriction by influencing salt-water homeostasis. Therefore, the purpose of the present study was to explore the association of single nucleotide polymorphisms (SNPs) in angiotensin I converting enzyme;ACE(rs4340), angiotensin II type1 receptor; AT1 (rs5186) and aldosterone synthase;CYP11B2(rs1799998) with LVD.Methods and results: The present study was carried out in two cohorts. The primary cohort included 308 consecutive patients with angiographically confirmed CAD and 234 healthy controls. Among CAD, 94 with compromised left ventricle ejection fraction (LVEF ≤ 45) were categorized as LVD. The ACE I/D, AT1 A1166C andCYP11B2T-344C polymorphisms were determined by PCR. Our results showed that ACE I/D was significantly associated with CAD but not with LVD. However, AT1 1166C variant was significantly associated with LVD (LVEF ≤ 45) (p value=0.013; OR=3.69), butCYP11B2(rs1799998) was not associated with either CAD or LVD. To validate our results, we performed a replication study in additional 200 cases with similar clinical characteristics and results again confirmed consistent findings (p value=0.020; OR=5.20).Conclusion: AT1 A1166C plays important role in conferring susceptibility of LVD.

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