Impact of overweight on myocardial infarct size in patients undergoing primary percutaneous coronary intervention: A magnetic resonance imaging study

Impact of body mass index on long-term outcomes in patients undergoing percutaneous coronary intervention stratified by diabetes mellitus: a retrospective cohort study

BACKGROUND

Patients with diabetes mellitus (DM) caused by obesity have increased in recent years. The impact of obesity on long-term outcomes in patients undergoing percutaneous coronary intervention (PCI) with or without DM remains unclear.

METHODS

We retrospectively analysed data from 1918 patients who underwent PCI. Patients were categorized into four groups based on body mass index (BMI, normal weight: BMI < 25 kg/m2; overweight and obese: BMI ≥ 25 kg/m2) and DM status (presence or absence). The primary endpoint was the occurrence of major adverse cardiac and cerebrovascular events (MACCE; defined as all-cause death, myocardial infarction, stroke, and unplanned repeat revascularization).

RESULTS

During a median follow-up of 7.0 years, no significant differences in MACCE, myocardial infarction, or stroke were observed among the four groups. Overweight and obese individuals exhibited lower all-cause mortality rates compared with normal-weight patients (without DM: hazard ratio [HR]: 0.54, 95% confidence interval [CI]: 0.37 to 0.78; with DM: HR: 0.57, 95% CI: 0.38 to 0.86). In non-diabetic patients, the overweight and obese group demonstrated a higher risk of unplanned repeat revascularization than the normal-weight group (HR:1.23, 95% CI:1.03 to 1.46). After multivariable adjustment, overweight and obesity were not significantly associated with MACCE, all-cause death, myocardial infarction, stroke, or unplanned repeat revascularization in patients with and without diabetes undergoing PCI.

CONCLUSION

Overweight and obesity did not demonstrate a significant protective effect on long-term outcomes in patients with and without diabetes undergoing PCI.

The prognostic value of myocardial salvage index by cardiac magnetic resonance in ST-segment elevation myocardial infarction patients: a systematic review and meta-analysis

OBJECTIVE

To assess the prognostic value of myocardial salvage index (MSI) by cardiac magnetic resonance (CMR) in ST-segment elevation myocardial infarction (STEMI) patients.

METHODS

We systematically searched PubMed, Embase, Web of Science, Cochrane Central, China National Knowledge Infrastructure, and Wanfang Data to identify primary studies reporting MSI in STEMI patients with major adverse cardiovascular events (MACE) comprised of death, myocardial reinfarction, and congestive heart failure. The MSI and MACE rates were pooled. The bias of risk was assessed using the Quality In Prognosis Studies tool. The evidence level was rated based on the meta-analysis of hazard ratio (HR) and 95% confidence interval (CI) of MSI for predicting MACE.

RESULTS

Eighteen studies were included covering twelve unique cohorts. Eleven cohorts measured MSI using T2-weighted imaging and T1-weighted late gadolinium enhancement, while one cohort applied T2-mapping and T1-mapping. The pooled MSI (95% CI) was 44% (39 to 49%; 11 studies, 2946 patients), and the pooled MACE rate (95% CI) was 10% (7 to 14%; 12 studies, 311/3011 events/patients). Seven prognostic studies overall showed low risk of bias. The HR (95% CI) per 1% increase of MSI for MACE was 0.95 (0.92 to 0.98; 5 studies, 150/885 events/patients), and HR (95% CI) of MSI < median versus MSI > median for MACE was 5.62 (3.74 to 8.43; 6 studies, 166/1570 events/patients), both rated as weak evidence.

CONCLUSIONS

MSI presents potential in predicting MACE in STEMI patients. The prognostic value of MSI using advanced CMR techniques for adverse cardiovascular events needs further investigation.

CLINICAL RELEVANCE STATEMENT

Seven studies supported the MSI to serve as a predictor for MACE in STEMI patients, indicating its potential as a risk stratification tool to help manage expectations for these patients in clinical practice.

KEY POINTS

• The pooled infarct size (95% CI) and area at risk (95% CI) were 21% (18 to 23%; 11 studies, 2783 patients) and 38% (34 to 43%; 10 studies, 2022 patients), respectively. • The pooled rates (95% CI) of cardiac mortality, myocardial reinfarction, and congestive heart failure were 2% (1 to 3%; 11 studies, 86/2907 events/patients), 4% (3 to 6%; 12 studies, 127/3011 events/patients), and 3% (1 to 5%; 12 studies, 94/3011 events/patients), respectively. • The HRs (95% CI) per 1% increase of MSI for cardiac mortality and congestive heart failure were 0.93 (0.91 to 0.96; 1 study, 14/202 events/patients) and 0.96 (0.93 to 0.99; 1 study, 11/104 events/patients), respectively, but the prognostic value of MSI for myocardial re-infraction has not been measured.

BMI Modifies Increased Mortality Risk of Post-PCI STEMI Patients with AKI

Mortality from acute ST elevation myocardial infarction (STEMI) was significantly reduced with the introduction of percutaneous catheterization intervention (PCI) but remains high in patients who develop acute kidney injury (AKI). Previous studies found overweight to be protective from mortality in patients suffering from STEMI and AKI separately but not as they occur concurrently. This study aimed to establish the relationship between AKI and mortality in STEMI patients after PCI and whether body mass index (BMI) has a protective impact. Between January 2008 and June 2016, two thousand one hundred and forty-one patients with STEMI underwent PCI and were admitted to the Tel Aviv Medical Center Cardiac Intensive Care Unit. Their demographic, laboratory, and clinical data were collected and analyzed. We compared all-cause mortality in patients who developed AKI after PCI for STEMI and those who did not. In total, 178 patients (10%) developed AKI and had higher mortality (p < 0.001). Logistic regression analysis was performed to determine the relationship between AKI, BMI, and mortality. AKI was significantly associated with both 30-day and overall mortality, while BMI had a significant protective effect. Survival analysis found a significant difference in 30-day and overall survival between patients with and without AKI with a significant protective effect of BMI on survival at 30 days. AKI presents a major risk for mortality and poor survival after PCI for STEMI, yet a beneficial effect of increased BMI modifies it.

Impact of Obesity on Microvascular Obstruction and Area at Risk in Patients After ST-Segment-Elevation Myocardial Infarction: A Magnetic Resonance Imaging Study

BACKGROUND

Better survival for overweight and obese patients after ST-segment elevation myocardial infarction (STEMI) has been demonstrated. The association between body mass index (BMI), microvascular obstruction (MVO), and area at risk (AAR) after STEMI was evaluated.

METHODS

A prospective observational study was performed to enrolled patients undergoing primary percutaneous coronary intervention (pPCI) for STEMI and cardiac magnetic resonance was performed within 5-7 days. Patients were classified as normal weight (18.5 ≤BMI <24.0 kg/m²), overweight (24.0 ≤BMI <28.0 kg/m²), or obese (BMI ≥28 kg/m²).

RESULTS

Among 225 patients undergoing pPCI, 67 (30.00%) were normal weight, 113 (50.22%) were overweight, and 45 (20.00%) were obese. BMI ≥28 kg/m² was significantly associated with less risk of MVO when compared with a normal BMI after multivariable adjustment (overweight: HR 0.29, 95% CI 0.13-0.68, p = 0.004). Compared with normal weight patients, obese and overweight patients tend to have larger hearts (greater left ventricular end-diastolic volume [LVEDV] and left ventricular [LV] mass). In adjusted analysis, increased BMI was significantly associated with a smaller AAR. In addition, obese patients had a smaller AAR (β = -0.252, 95% CI -20.298- -3.244, p = 0.007) and AAR, % LV mass (β = -0.331, 95% CI -0.211- -0.062, p < 0.001) than normal weight patients.

CONCLUSION

Obesity (BMI ≥28 kg/m²) is independently associated with lower risks of MVO and a smaller AAR, % LV mass than normal weight patients among subjects undergoing pPCI for STEMI.

Association of Body Mass Index with Mortality in Patients with Cardiogenic Shock following Acute Myocardial Infarction: A Contemporary Danish Cohort Analysis

AIMS

The obesity paradox suggests a better prognosis in overweight or obese patients with heart failure and acute myocardial infarction (AMI) than patients with normal weight. Few studies have investigated the association between BMI and mortality in patients with AMI complicated by cardiogenic shock (AMICS). The aim of this study was to evaluate the association between BMI and 30-day mortality in patients with AMICS.

METHODS AND RESULTS

A retrospective study of 1,716 patients with AMICS treated at 2 tertiary centers in south-eastern Denmark between 2010 and 2017. Patients undergoing revascularization and who were admitted to the intensive care unit were included (n = 1,216). BMI was available in 1,017 patients (83.6%). Patients were divided according to the WHO classification as normal weight BMI <24.9 kg/m2 (n = 453), overweight BMI 25-29.9 kg/m2 (n = 391), obese class 1 BMI 30-34.9 kg/m2 (n = 131), and obese class 2 + 3 BMI >35 kg/m2 (n = 42). Differences in baseline characteristics, in-hospital treatment, and the primary outcome of all-cause mortality at 30 days were examined. Obese patients had more comorbidities such as diabetes, hypertension, and dyslipidemia than patients with normal weight. Need for renal replacement therapy was higher among obese patients (normal weight, 19% vs. obese class 2 + 3, 35%, p = 0.02); otherwise, no difference in management was found. No difference in 30-day mortality was observed between groups (normal weight 44%, overweight 38%, obese class 1 41%, and obese class 2 + 3 45% at 30 days; ns).

CONCLUSIONS

Thirty-day mortality in patients with AMICS was not associated with the BMI category. Thus, evidence of an "obesity paradox" was not observed in this contemporary cohort of patients with AMICS in Denmark.

Association Between High Body Mass Index and Mortality Following Myocardial Injury After Noncardiac Surgery

BACKGROUND

Despite an association between obesity and increased risks for various diseases, obesity has been paradoxically reported to correlate with improved mortality in patients with established cardiovascular disease. However, its effect has not been evaluated to date in patients with myocardial injury after noncardiac surgery (MINS).

METHODS

From January 2010 to June 2019, of a total of 35,269 adult patients with postoperative cardiac troponin level data, 5633 (16.0%) patients had MINS as diagnosed by postoperative cardiac troponin I above the 99th-percentile upper reference of 40 ng·L-1 using the TnI-Ultra immunoassay. Patients with MINS were divided into 3 groups according to body mass index (BMI), with 3246 (57.6%) were in the normal (18.5-25 kg·m-2), 425 (7.5%) in the low BMI (<18.5 kg·m-2), and 1962 (34.8%) in the high BMI (≥25 kg·m-2) groups, respectively. The primary outcome was mortality during the first year after surgery, and the mortality during 30 days was also compared.

RESULTS

Following adjustment for confounding with inverse probability of treatment weighting, mortality within the first year appeared to be significantly lower in the high BMI group compared with the normal (14.8% vs 20.9%; hazard ratio [HR], 0.75; 95% confidence interval [CI], 0.66-0.85; P < .001) and the low BMI (14.8% vs 25.6%; HR: 0.56; 95% CI, 0.48-0.66; P < .001) groups.

CONCLUSIONS

High BMI may be associated with decreased mortality following MINS. Further investigations are needed to support this finding.

BMI, Infarct Size, and Clinical Outcomes Following Primary PCI: Patient-Level Analysis From 6 Randomized Trials

OBJECTIVES

The aim of this study was to examine the association between body mass index (BMI), infarct size (IS) and clinical outcomes.

BACKGROUND

The association between obesity, IS, and prognosis in patients undergoing primary percutaneous coronary intervention (pPCI) for ST-segment elevation myocardial infarction is incompletely understood.

METHODS

An individual patient-data pooled analysis was performed from 6 randomized trials of patients undergoing pPCI for ST-segment elevation myocardial infarction in which IS (percentage left ventricular mass) was assessed within 1 month (median 4 days) after randomization using either cardiac magnetic resonance (5 studies) or ^99mTc sestamibi single-photon emission computed tomography (1 study). Patients were classified as normal weight (BMI <25 kg/m²), overweight (25 kg/m² ≤BMI <30 kg/m²), or obese (BMI ≥30 kg/m²). The multivariable models were adjusted for age, sex, hypertension, hyperlipidemia, current smoking, left main or left anterior descending coronary artery infarct, baseline TIMI (Thrombolysis In Myocardial Infarction) flow grade 0 or 1, prior myocardial infarction, symptom-to-first device time, and study.

RESULTS

Among 2,238 patients undergoing pPCI, 644 (29%) were normal weight, 1,008 (45%) were overweight, and 586 (26%) were obese. BMI was not significantly associated with IS, microvascular obstruction, or left ventricular ejection fraction in adjusted or unadjusted analysis. BMI was also not associated with the 1-year composite risk for death or heart failure hospitalization (adjusted hazard ratio: 1.21 [95% confidence interval: 0.74 to 1.71] for overweight vs. normal [p = 0.59]; adjusted hazard ratio: 1.21 [95% confidence interval 0.74 to 1.97] for obese vs. normal [p = 0.45]) or for death or heart failure hospitalization separately. Results were consistent when BMI was modeled as a continuous variable.

CONCLUSIONS

In this individual patient-data pooled analysis of 2,238 patients undergoing pPCI for ST-segment elevation myocardial infarction, BMI was not associated with IS, microvascular obstruction, left ventricular ejection fraction, or 1-year rates of death or heart failure hospitalization.

Prognostic value of the myocardial salvage index measured by T2-weighted and T1-weighted late gadolinium enhancement magnetic resonance imaging after ST-segment elevation myocardial infarction: A systematic review and meta-regression analysis

In all patients with ST-segment elevation myocardial infarction, risk stratification should be performed before discharge. The measurement of therapy efficiency with magnetic resonance imaging has been proposed as part of the risk assessment, but it has not been adopted widely. This meta-analysis was conducted to summarize published data on the prognostic value of the proportion of salvaged myocardium inside previously ischemic myocardium (myocardial salvage index) measured by T2-weighted and T1-weighted late gadolinium enhancement magnetic resonance imaging after ST-segment elevation myocardial infarction. Random and mixed effects models were used for analyzing the data of 10 studies with 2,697 patients. The pooled myocardial salvage index, calculated as the proportion of non-necrotic myocardium inside edematous myocardium measured by T2-weighted and T1-weighted late gadolinium enhancement MRI, was 43.0% (95% confidence interval: 37.4, 48.6). The pooled length of follow-up was 12.3 months (95% confidence interval: 7.0, 17.6). The pooled incidence of major cardiac events during follow-up, defined as cardiac death, nonfatal myocardial infarction, or admission for heart failure, was 10.6% (95% confidence interval: 5.7, 15.5). The applied mixed effects model showed an absolute decrease of 1.7% in the incidence of major cardiac events during follow-up (95% confidence interval: 1.6, 1.9) with every 1% of increase in the myocardial salvage index. The heterogeneity between studies was considerable (τ = 21.3). Analysis of aggregated follow-up data after ST-segment elevation myocardial infarction suggests that the myocardial salvage index measured by T2-weighted and T1-weighted late gadolinium enhancement magnetic resonance imaging provides prognostic information on the risk of major cardiac events, but considerable heterogeneity exists between studies.

Evaluation of the impact of statin therapy on the obesity paradox in patients with acute myocardial infarction: A propensity score matching analysis from the Korea Acute Myocardial Infarction Registry

The phenomenon of obesity paradox after acute myocardial infarction (AMI) has been reported under strong recommendation of statin therapy. However, the impact of statin therapy on this paradox has not been investigated. This study investigated the impact of statin therapy on 1-year mortality according to obesity after AMI. A total of 2745 AMI patients were included from the Korea Acute Myocardial Infarction Registry after 1:4 propensity score matching analysis (n = 549 for nonstatin group and n = 2196 for statin group). Primary and secondary outcomes were all-cause and cardiac death, respectively. During 1-year follow-up, the incidence of all-cause (8.4% vs 3.7%) and cardiac (6.2% vs 2.3%) death was higher in nonstatin group than in statin (P < .001, respectively). In nonstatin group, the incidence of all-cause (7.2% vs 9.0%) and cardiac (5.5% vs 6.5%) death did not differ significantly between obese and nonobese patients. However, in statin group, obese patients had lower 1-year rate of all-cause (1.7% vs 4.8%) and cardiac (1.2% vs 2.9%) death (P < .05, respectively), and lower cumulative rates by Kaplan-Meier analysis of all-cause and cardiac death compared with nonobese patients (log-rank P < .05, respectively). The overall risk of all-cause death was significantly lower in obese than in nonobese patients only in statin group (hazard ratio: 0.35; P = .001). After adjusting for confounding factors, obesity was independently associated with decreased risk of all-cause death in statin group. In conclusion, the greater benefit of statin therapy for survival in obese patients is further confirmation of the obesity paradox after AMI.

Comparison of 2-year mortality according to obesity in stabilized patients with type 2 diabetes mellitus after acute myocardial infarction: results from the DIAMOND prospective cohort registry

Background

After acute myocardial infarction (AMI), the replicated phenomenon of obesity paradox, i.e., obesity appearing to be associated with increased survival, has not been evaluated in stabilized (i.e., without clinical events within 1 month post AMI) Asian patients with diabetes mellitus (DM).

Methods

Among 1192 patients in the DIabetic Acute Myocardial InfarctiON Disease (DIAMOND) Korean multicenter registry between April 2010 and June 2012, 2-year cardiac and all-cause death were compared according to obesity (body mass index ≥25 kg/m²) in 1125 stabilized DM patients.

Results

Compared with non-obese DM patients (62 % of AMI patients), obese DM patients had: higher incidence of dyslipidemia (31 vs. 24 %, P < 0.01); lower incidence of chronic kidney disease (26 vs. 33 %) (P < 0.01); higher left ventricular ejection fraction after AMI (53 ± 11 vs. 50 ± 12 %, P < 0.001); and lower 2-year cardiac and all-cause death occurrence (0.7 vs. 3.6 % and 1.9 vs. 5.2 %, both P < 0.01) and cumulative incidence in Kaplan–Meier analysis (P < 0.005, respectively). Likewise, both univariate and multivariate Cox hazard regression analyses adjusted for the respective confounders showed that obesity was associated with decreased risk of both cardiac [HR, 0.18 (95 % CI 0.06–0.60), P = 0.005; and 0.24 (0.07–0.78), P = 0.018, respectively] and all-cause death [0.34 (0.16–0.73), P = 0.005; and 0.44 (0.20–0.95), P = 0.038].

Conclusions

In a Korean population of stabilized DM patients after AMI, non-obese patients appear to have higher cardiac and all-cause mortality compared with obese patients after adjusting for confounding factors.

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-015-0305-1) contains supplementary material, which is available to authorized users.

Obesity and coronary artery disease: evaluation and treatment

With the increasing prevalence of obesity, clinicians are now facing a growing population of patients with specific features of clinical presentation, diagnostic challenges, and interventional, medical, and surgical management. After briefly discussing the effect of obesity on atherosclerotic burden in this review, we will focus on strategies clinicians might use to ensure better outcomes when performing revascularization in obese and severely obese patients. These patients tend to present comorbidities at a younger age, and their anthropometric features might limit the use of traditional cardiovascular risk stratification approaches for ischemic disease. Alternative techniques have emerged, especially in nuclear medicine. Positron emission tomography-computed tomography might be the diagnostic imaging technique of choice. When revascularization is considered, features associated with obesity must be considered to guide therapeutic strategies. In percutaneous coronary intervention, a radial approach should be favoured, and adequate antiplatelet therapy with new and more potent agents should be initiated. Weight-based anticoagulation should be contemplated if needed, with the use of drug-eluting stents. An "off-pump" approach for coronary artery bypass grafting might be preferable to the use of cardiopulmonary bypass. For patients who undergo bilateral internal thoracic artery grafting, harvesting using skeletonization might prevent deep sternal wound infections. In contrast to percutaneous coronary intervention, lower surgical bleeding has been observed when lean body mass is used for perioperative heparin dose determination.