Role of coronary spasm in the genesis of myocardial infarction: Study of a case treated by isosorbide dinitrate in situ then by transluminal angioplasty

Rationale: Tetany is a common, serious, well-established endocrinal and metabolic hypocalcemic disorder. Chest tetany is a novel metabolic term in hypocalcemia characterized by acute severe twisting chest pain. Movable phenomenon (Yasser’s phenomenon) is a new phenomenon that is usually associated with hypocalcemia. oxygenation may have a role in the management of coronary artery spasm. Patient concerns: A middle-aged farmer smoker male patient presented to physician outpatient clinic with tetany, mimic high lateral myocardial infarction, mirror electrocardiographic change, Movable phenomenon (Yasser’s phenomenon), and coronary artery spasm. Diagnosis: Mimic high lateral myocardial infarction in chest tetany with mirror electrocardiographic change, Movable phenomenon (Yasser’s phenomenon), and coronary artery spasm. Interventions: Electrocardiography, oxygenation, IV calcium injection, and echocardiography. Outcomes: Acute dramatic clinical and electrocardiographic improvement had happened. Lessons: The reversal of mirror electrocardiographic change, reversal of ST-segment depression coronary artery spasm, and normalization of Movable phenomenon (Yasser’s phenomenon) after oxygenation. It signifies the role of oxygen in both coronary artery spasm and tetany. Mirror local electrocardiographic change is a novel described expression that may reflect the myocardial polarity in this chest tetany.

Download Full-text

Novel role of aminopeptidase-A in angiotensin-(1–7) metabolism post myocardial infarction

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00911.2013 ◽

2014 ◽

Vol 306 (7) ◽

pp. H1032-H1040 ◽

Cited By ~ 9

Author(s):

Mahmoud S. Alghamri ◽

Mariana Morris ◽

J. Gary Meszaros ◽

Khalid M. Elased ◽

Nadja Grobe

Keyword(s):

Myocardial Infarction ◽

Renin Angiotensin System ◽

Substrate Affinity ◽

Mouse Heart ◽

Ang Ii ◽

Vitro Assay ◽

Aminopeptidase A

Aminopeptidase-A (APA) is a less well-studied enzyme of the renin-angiotensin system. We propose that it is involved in cardiac angiotensin (ANG) metabolism and its pathologies. ANG-(1–7) can ameliorate remodeling after myocardial injury. The aims of this study are to 1) develop mass spectrometric (MS) approaches for the assessment of ANG processing by APA within the myocardium; and 2) investigate the role of APA in cardiac ANG-(1–7) metabolism after myocardial infarction (MI) using sensitive MS techniques. MI was induced in C57Bl/6 male mice by ligating the left anterior descending (LAD) artery. Frozen mouse heart sections (in situ assay) or myocardial homogenates (in vitro assay) were incubated with the endogenous APA substrate, ANG II. Results showed concentration- and time-dependent cardiac formation of ANG III from ANG II, which was inhibited by the specific APA inhibitor, 4-amino-4-phosphonobutyric acid. Myocardial APA activity was significantly increased 24 h after LAD ligation (0.82 ± 0.02 vs. 0.32 ± 0.02 ρmol·min−1·μg−1, MI vs. sham, P < 0.01). Both MS enzyme assays identified the presence of a new peptide, ANG-(2–7), m/z 784, which accumulated in the MI (146.45 ± 6.4 vs. 72.96 ± 7.0%, MI vs. sham, P < 0.05). Use of recombinant APA enzyme revealed that APA is responsible for ANG-(2–7) formation from ANG-(1–7). APA exhibited similar substrate affinity for ANG-(1–7) compared with ANG II { Km (ANG II) = 14.67 ± 1.6 vs. Km [ANG-(1–7)] = 6.07 ± 1.12 μmol/l, P < 0.05}. Results demonstrate a novel role of APA in ANG-(1–7) metabolism and suggest that the upregulation of APA, which occurs after MI, may deprive the heart of cardioprotective ANG-(1–7). Thus APA may serve as a potentially novel therapeutic target for management of tissue remodeling after MI.

Download Full-text