Independent association between symptom onset time and infarct size in patients with ST-elevation myocardial infarction undergoing primary percutaneous coronary intervention

Relationship between primary percutaneous coronary intervention time of day, infarct size, microvascular obstruction and prognosis in ST-segment elevation myocardial infarction

BACKGROUND

Whether the time of day of primary percutaneous coronary intervention (pPCI) in patients with ST-segment elevation myocardial infarction (STEMI) is associated with infarct size, microvascular obstruction (MVO), and prognosis is uncertain. We compared infarct size assessed by cardiac MRI (CMR) and clinical outcomes in STEMI patients according to the pPCI time of day from a large, individual patient-data pooled database.

METHODS

We pooled patient-level data from five randomized pPCI trials in which infarct size was measured within 1 month by CMR. Patients were categorized according to the pPCI time of day.

RESULTS

Among 1519 patients with STEMI, 794 (52.2%) underwent pPCI between 8:00 h and 15:59 h, 431 (28.4%) between 16:00 h and 23:59 h, and 294 (19.4%) between 24:00 h and 7:59 h. Infarct size was assessed in 1331 patients at a median of 3.0 days (interquartile range 2.0-5.0) after pPCI. Compared with patients who underwent PCI between 8:00 h and 15:59 h, infarct size was not significantly different for patients undergoing PCI from 16:00 h to 23:59 h [adjusted difference -0.7%, 95% confidence interval (CI) -3.1 to 1.7%, P = 0.46] or 24:00 h to 7:59 h (adjusted difference 0.9%, 95% CI -1.2 to 3.1%, P = 0.29). The time of day of pPCI was also unrelated to MVO and the 1-year risks of death or heart failure hospitalization.

CONCLUSION

In this large-scale, individual patient data pooled analysis, no association was found between the time of day of pPCI and infarct size, MVO, or prognosis after STEMI.

Impact of time of onset of symptom of ST-segment elevation myocardial infarction on 1-year rehospitalization for heart failure and mortality

Circadian patterns in ST-segment elevation myocardial infarction (STEMI) patients have been previously reported, but little is known about the impact of time dependence of symptom onset on long-term prognosis. Our study population consisted of 11,731 STEMI patients treated by primary percutaneous coronary intervention (PPCI), enrolled in the Singapore Myocardial Infarction Registry (SMIR). Analysis of STEMI incidence trends over the 24-hour period showed the highest rate of symptom onset in the morning, with the peak incidence at 09:00 am. Patients with symptom onset in between 00:00 am-5:59 am showed the highest prevalence of diabetes (P = .010) and anterior STEMI (P < .001) and had the longest ischemic time (P < .001). After adjusting for confounders, we found an association between time of symptom onset of STEMI and rehospitalization for heart failure (HF) at 1 year, with symptom onset between 06:00 pm-11:59 pm and 00:00 am-05:59 am having an estimated 30% to 50% higher risk of rehospitalization for HF at 1 year. Moreover, symptom onset remained a predictor of worse prognosis only in the subgroup of patients with symptoms lasting longer than 120 minutes. The results of this study demonstrate for the first time that rehospitalization for HF in STEMI patients treated with PPCI has a dependence on the time of onset of symptoms, with prolonged ischemia time playing a pivotal role. This may be an additional risk factor to identify those who warrant closer monitoring and more rigorous optimization of their treatment at follow-up, to improve their outcomes.

Time-of-day at symptom onset was not associated with infarct size and long-term prognosis in patients with ST-segment elevation myocardial infarction

Background

ST-segment elevation myocardial infarction (STEMI) displays circadian variability with the highest incidence in the morning hours. Data on whether the time-of-day at symptom onset affects infarct size or patients’ long-term prognosis are conflicting. We sought to investigate the association of time-of-day at symptom onset with infarct size or long-term mortality in patients with STEMI undergoing primary percutaneous coronary intervention (PPCI).

Methods

This study included 1206 STEMI patients undergoing PPCI. All patients underwent single photon emission computed tomography (SPECT) imaging with 99mTc-sestamibi before and 7–14 days after PPCI. The co-primary endpoints were final infarct size on day 10 after STEMI and all-cause mortality at 5-year follow-up. Time-of-day at symptom onset of STEMI was categorized in 6-h intervals.

Results

In patients presenting from 0 to 6 h, 6 to 12 h, 12 to 18 h, and 18 to 24 h, the infarct sizes (median [25th–75th percentiles]) were 10.0 [3.0–24.7], 10.0 [3.0–24.0], 10.0 [3.0–22.0], and 9.0 [3.0–21.0] of the left ventricle, respectively (p = 0.87); the Kaplan–Meier estimates of 5-year all-cause mortality were 13.6%, 8.7%, 13.7% and 9.3%, respectively (log-rank test p = 0.30). After adjustment, time-of-day was not associated with infarct size (p ≥ 0.76 for comparisons with infarct size from reference [6–12 h] time interval) or 5-year all-cause mortality (p ≥ 0.25 for comparisons with mortality from reference [6–12 h] time interval). Time-of-day at symptom onset of STEMI was not associated with differences in the recovery of left ventricular ejection fraction 6 months after STEMI.

Conclusions

In patients with STEMI undergoing PPCI, time-of-day at symptom onset was neither associated with scintigraphic infarct size, left ventricular ejection fraction recovery at 6 months nor with 5-year mortality.

Electronic supplementary material

The online version of this article (10.1186/s12967-019-1934-z) contains supplementary material, which is available to authorized users.

Circadian Periodicity of Ischemic Heart Disease: A Systematic Review of the Literature

The authors performed a MEDLINE search to identify reports, published during the last 20 years, focused on circadian variation of acute myocardial infarction (AMI), and prevalence and the ratios between the number of events per hour during the morning and the other hours of the day were calculated. Despite the optimization of interventional and medical therapy of AMI since the first reports of circadian patterns in AMI occurrence, it was found that such a pattern still exists and that AMI happens most frequently in the morning hours.

Factors attributed to the higher in-hospital mortality of ST elevation myocardial infarction patients admitted during off-hour in comparison with those during regular hour

Background

In-hospital mortality of patients with ST elevation myocardial infarction (STEMI) admitted during off-hour was reported higher than those admitted during regular hour, but which factors cause the difference remains largely unknown though the difference in medical resources was often accused.

Methods and results

This registry-based study recruited 7456 STEMI patients prospectively from 99 level two hospitals across China. Generalized linear mixed models were applied to quantify the risk of in-hospital death attributed to admission time and the explainers of its change, accounting for the clustering of patients within hospitals. There were 45.2% patients admitted during regular hour and 54.8% during off-hour. In-hospital mortality was 7.0% for patients admitted during regular hour and 8.3% for those during off-hour (p<0.05). Generalized linear mixed models adjusting for age, gender and education showed that patients’ disease severity at admission and medical treatments received after admission could explain the risk difference attributed to admission time by 55% and 20%, respectively. After all factors accounted, the residual relative risk difference left only 6% (adjusted OR = 0.94) and became no longer significant.

Conclusions

The regular-and-off-hour mortality difference exists among STEMI patients in Chinese level two hospitals, which could be attributed primarily to disease severity at admission and secondly to the poorer medical treatments. These results call for public attention to the more severity of STEMI patients admitted during off-hour in addition to improving medical resources for STEMI at off-hour.

Chronobiology of Takotsubo Syndrome and Myocardial Infarction: Analogies and Differences

Several pathophysiologic factors, not harmful if taken alone, are capable of triggering unfavorable events when presenting together within the same temporal window (chronorisk), and the occurrence of many cardiovascular events is not evenly distributed in time. Both acute myocardial infarction and takotsubo syndrome seem to exhibit a temporal preference in their onset, characterized by variations according to time of day, day of the week, and month of the year, although with both analogies and differences.

Circadian variation in acute myocardial infarct size assessed by cardiovascular magnetic resonance in reperfused STEMI patients

OBJECTIVE

Clinical studies using serum cardiac biomarkers to investigate a circadian variation in acute myocardial infarct (MI) size in ST-segment elevation myocardial infarction (STEMI) patients reperfused by primary percutaneous coronary intervention (PPCI) have produced mixed results. We aimed to investigate this phenomenon using acute MI size measured by cardiovascular magnetic resonance (CMR).

METHODS

Patient-level data was obtained from 4 randomized controlled trials investigating the MI-limiting effects of cardioprotective therapies in this pooled analysis. The primary analysis was performed in those patients with no pre-infarct angina; duration of ischemia >60min and <360min; Thrombolysis In Myocardial Infarction (TIMI) flow pre-PPCI ≤1; TIMI flow post-PPCI 3; and no collateral flow.

RESULTS

169 out of 376 patients with CMR data met the inclusion criteria for the primary analysis. A 24-hour circadian variation in acute MI size as a % of the area-at-risk (%AAR), after adjusting for confounders, was observed with a peak and nadir MI size in patients with symptom onset between 00:00 and 01:00 and between 12:00 and 13:00 respectively (difference from the average MI size 5.2%, 95%CI 1.1-9.4%; p=0.013). This was associated with a non-significant circadian variation in left ventricular ejection fraction (LVEF) (difference from the average LVEF 5.9%, 95%CI -0.6-2.2%, p=0.073). There was no circadian variation in MI size or LVEF in the whole cohort.

CONCLUSIONS

We report a circadian variation in acute MI size assessed by CMR in a subset of STEMI patients treated by PPCI, with the largest and smallest MI size occurring in patients with symptom onset between 00:00 and 01:00 and between 12:00 and 13:00 respectively.