Spontaneous dissection of proximal left main coronary artery in a healthy adolescent presenting with syncope: A case report.

BACKGROUND: Spontaneous coronary artery dissection (SCAD) is a frequent cause of acute coronary syndrome in young to middle-aged women with few or no traditional cardiovascular risk factors. Chest pain is the most frequently described presenting symptom, but syncope is extremely rare. Herein, we report on a 16-year-old girl who presented with an episode of syncope occurring during a race. Despite significantly elevated troponin level, the diagnosis of the left main coronary artery SCAD with cardiogenic shock was delayed. CASE SUMMARY: A 16-year-old girl presented with an episode of syncope. Myocardial injury markers were positive. Echocardiography showed a mildly reduced left ventricular ejection fraction (50%). Although initially stable, she later experienced recurrent chest pain accompanying precordial ST segment elevation with dynamic changes and developed cardiogenic shock, necessitating emergent revascularization. Coronary angiography demonstrated almost total occlusion at the ostium and proximal segment of the left main trunk coronary artery (LMT). Intravascular ultrasound confirmed a false lumen with prominent dissection in the LMT. Percutaneous coronary intervention assisted by intra-aortic balloon pump was conducted in the LMT. A 3.5 mm × 24 mm everolimus-eluting stent was deployed to the focal lesions of the LMT. A postprocedural electrocardiogram showed alleviation of the precordial ST-segment elevation. The diagnosis of SCAD was confirmed. Transthoracic echocardiography showed an improved left ventricular ejection fraction (57%). The patient was asymptomatic during the 24-mo. follow-up period. CONCLUSION: SCAD should always be considered in the differential diagnosis of acute coronary syndrome presentations in low-risk patients, regardless of age.

[Effect of atorvastatin on ACE2 expression in pressure overload induced cardiac hypertrophy in rats].

OBJECTIVE: To investigate the effect of atorvastatin on the expression of angiotensin converting enzyme 2 (ACE2) mRNA and its protein in hypertrophic myocardium in rats. METHODS: Suprarenal abdominal aortic coarctation was performed to create the pressure overload induced left ventricular hypertrophy model in rats. RESULTS: Rats were randomly divided into 5 groups: (1) normal control group (Group A); (2) normal control group treated with atorvastatin [(5 mg/(kg.dd), Group B]; (3) sham group (Group C); (4) atorvastatin given orally by gastric gavage for 4 weeks [5 mg/(kg.dd),Group D]; (5) vehicle group (Group E). Stained pathological section was observed under light microscope to measure cardiomyocyte diameter transversa and collagen volume fraction. ACE2 mRNA and its protein expression were detected by real-time RT-PCR and Western blot. Compared with Group A,B, and C, the left ventricular mass index, cardiomyocyte diameter transversa and collagen volume fraction in Group E increased statistically (P< 0.01), ACE2 mRNA and its protein expression also elevated remarkably (P< 0.01). Compared with Group E, the above mentioned indexes in Group D reduced significantly (P< 0.01). CONCLUSION: ACE2 mRNA and its protein expression increase significantly in hypertrophic myocardium in rats; atorvastatin can attenuate cardiac hypertrophy due to pressure overload in rats effectively, and part of this anti-hypertrophy effect may be attributed to decrease ACE2 mRNA and protein expression.