The Effect of Smoking on Myocardial Performance Index in Middle-Aged Males after First Acute Myocardial Infarction

Meta-Analysis Comparing Outcomes of Smokers Versus Nonsmokers With Acute Coronary Syndrome Underwent Percutaneous Coronary Intervention

Several studies have found improved mortality in smokers after acute coronary syndrome (ACS) especially in the thrombolytic era. We aimed to assess the association of smoking status with mortality and cardiovascular outcomes in patients with ACS treated with percutaneous coronary intervention (PCI). We searched PubMed, EMBASE, CINAHL, and Cochrane CENTRAL for randomized controlled trials since inception through February 15, 2018 and used random effects model for analysis. The outcomes analyzed were all-cause mortality, major adverse cardiac events (MACE), myocardial infarction, and target vessel revascularization at 1 month and 1 year. We included 17 randomized and nonrandomized studies with a total of 55,491 patients with 21,989 smokers' and 33,502 nonsmokers. In ACS patients treated with PCI, smokers were found to have lower mortality than nonsmokers at 30-day ([2.3% vs 3.3%; Odds ratio; 0.54; 95% confidence interval: 0.39 to 0.76; p <0.001, I² = 74%] and 1-year [2.3% vs 3.6%; Odds ratio 0.54 (0.3 to 0.7); p <0.001, I² = 77%]. Meta-regression showed lower mortality in smokers was associated with younger age, man gender, and lower prevalence of diabetes mellitus. No significant differences were observed in myocardial infarction, MACE, and target-vessel revascularization between smokers and nonsmokers. In conclusion, smoking is associated with lower mortality but not MACE in ACS patients treated with PCI at 1-month and 1-year. This association with mortality was strongly associated with younger age, man gender, prevalence of diabetes mellitus, and extent of coronary artery disease.

Circadian Rhythm of Infarct Size and Left Ventricular Function Evaluated with Tissue Doppler Echocardiography in ST Elevation Myocardial Infarction

BACKGROUND

We aimed to investigate the circadian rhythm on left ventricular (LV) function and infarct size, according to the onset of ST elevation myocardial infarction (STEMI), with echocardiography in patients with first STEMI successfully revascularised with primary percutaneous coronary intervention (PCI).

METHODS

We conducted a retrospective analysis of 252 STEMI patients. Patients were divided into the four, six-hour periods of the day. Conventional and tissue Doppler imaging (TDI) echocardiography were performed within 48hours after onset of chest pain. The average of peak systolic myocardial velocities (Sm) in each of the four myocardial segments and LV ejection fraction (LVEF) were calculated.

RESULTS

A negative linear correlation was shown between CK-MB levels and Sm (r= -0.209, p=0.001). There was an oscillation between time of day and average of Sm. The lowest Sm and largest infarct size were in the period of 06:00-noon compared with period of noon-18:00 and 18:00-midnight (p=0.029 and p=0.031, respectively). A secondary analysis showed that both LVEF and Sm were lower in the midnight-noon group compared with the noon-midnight group (44.9±7.3% versus 47.3±7.9%, p=0.018, and 7.6±1.4cm/s versus 8.2±1.6cm/s, p=0.003, respectively).

CONCLUSIONS

This study has shown that there was a circadian rhythm of infarct size and LV function evaluated by echocardiography according to time of STEMI onset. The largest infarct size and poor LV function occurred in the midnight-noon period, in particular in the 06:00-noon period.