[Correlation of heart rate turbulence to coronary lesions and its changes following percutaneous transluminal coronary angioplasty].

OBJECTIVE: To investigate the correlation between heart rate turbulence (HRT) and coronary lesion and the effects of percutaneous transluminal coronary angioplasty (PTCA) on HRT. METHODS: This study involved 150 patients undergoing 24-hour ambulatory electrocardiography (AECG) and elective coronary angiography (CAG). AECG was monitored on the first day and 7 days after PTCA in 108 patients with positive CAG findings, and the variation of HRT and cardiac functions were observed. The turbulence onset (TO), turbulence slope (TS) and turbulence timing (TT) of each section of HRT were calculated, analyzed and compared. RESULTS: The values of TO and TT were significantly higher and TS significantly lower in CAG-positive group than in CAG-negative group (P<0.05 or 0.001). Significant difference was found in TO, TS and TT between patients with single and multiple coronary lesions (P<0.05 and 0.001). The values of TO, TS and TT on the first day after PTCA improved significantly in comparison with the those before PTCA in patients with single and multiple coronary lesions (P<0.001). Postoperative follow-up of the patients revealed obviously attenuated HRT in patients with left cardiac insufficiency compared with the patients with normal cardiac function (P<0.05). CONCLUSION: HRT is correlated to the severity of the coronary lesions and shows significant improvement after PTCA. Cardiac function insufficiency is an important factor affecting the HRT attenuation.

[Relation of plasma brain natriuretic peptide to serum creatine kinase MB level in patients with acute myocardial infarction following primary percutaneous coronary intervention].

OBJECTIVE: To study the relation between plasma brain natriuretic peptide (BNP) and serum creatine kinase MB (CK-MB) level in patients with acute myocardial infarction (AMI) following primary percutaneous coronary intervention (PCI). METHODS: Sixty-three consecutive patients with AMI were divided into two groups according to the timing of PCI, namely direct PCI and indirect PCI groups. Plasma BNP levels were measured in all patients on admission and at 4, 24 and 48 h after admission. The CK-MB level was measured every 3 h on the first day of hospitalization, every 6 h on the second day and every 12 h on the third day. RESULTS: BNP level increased gradually following admission and began to decrease 48 h after admission in the two groups of patients. The peak BNP level occurred at 24 h after admission, and the BNP levels in patients of indirect PCI group were significantly higher than that of direct PCI group at 4, 24 and 48 h after admission. The peak CK-MB level of the direct PCI group occurred significantly earlier than that of the indirect group. CONCLUSION: Plasma BNP level may serve as an important objective indicator for recanalization of the infarct-related arteries following PCI in the early stage of AMI, which can help in the decision on clinical treatment plans for AMI.