One-year unplanned readmission after percutaneous coronary intervention in ST-elevation myocardial infarction: rates, causes and predictors

Introduction and aim

Unplanned readmission after percutaneous coronary intervention (PCI) in patients with ST-elevation myocardial infarction (STEMI) has a significant impact on the healthcare system. Nevertheless, most of the previous literature evaluated readmission within one month only post PCI without assessing the long-term readmission rates and predictors post-PCI. Therefore, we conducted a retrospective observational study to determine the rates, causes, and predictors of readmission post PCI among patients with STEMI over 1-year follow-up.

Methods

We conducted a single-center retrospective observation cohort study. Study population included all patients who were admitted to the hospital with diagnosis of STEMI and underwent PCI during the same admission (index admission) and discharged alive in the period between Jan 1st, 2016 and Sep 30th, 2018. Patients were divided into two groups: those who had one or more unplanned readmission within one year after PCI and those who were not readmitted. Rates and causes of readmission within one year following PCI were reported. Predictors of readmission post-PCI were assessed using multivariate logistic regression and reported as odds ratio (OR) with p<0.05 indicating statistical significance.

Results

A total of 1257 patients were included in our retrospective analysis. Most of the patients were male (95.9%). The mean age of the study population was 51±10. The most frequent culprit vessel was left anterior descending artery (LAD) in 56.3%. The median troponin T upon presentation was 47 ng/L [interquartile range: 171], with 25th percentile of 17 ng/L and 75th percentile of 2197 ng/L. Although around 70% of patients had reduced ejection fraction during the index admission, only 13.4% of the study population had clinical heart failure (HF). The unplanned readmission rate within one year post PCI was 11.5%, with 8.2% due to cardiac readmission while the remaining 3.3% due to non-cardiac causes. The most common cardiac causes for readmission were acute coronary syndrome and HF as shown in Table 1. As demonstrated in Table 2, positive predictors for all-cause readmission within one year after PCI among patients with STEMI were female gender (aOR= 4.14, 95% CI 2.10–8.18; p-value<0.001), chronic kidney disease (aOR= 2.76, 95% CI 1.07–7.08; p-value= 0.035), PCI using more than one stent (aOR= 1.66, 95% CI 1.09–2.55; p-value= 0.019) and clinical HF during index admission (aOR= 2.36, 95% CI 1.49–3.74; p-value<0.001).

Conclusion

The rate of one-year unplanned readmissions after PCI among patients with STEMI was 11.5%, with acute coronary syndrome and HF as most common causes of cardiac readmission. We found that female gender, chronic kidney disease, PCI with more than one stent and clinical HF were associated with a significantly increased likelihood of readmission after PCI among patients with STEMI which may warrant close and frequent follow-up for these populations.

Funding Acknowledgement

Type of funding sources: None.

Mitral regurgitation increases readmission due to heart failure after percutaneous coronary intervention among patients with ST-elevation myocardial infarction: a retrospective data review

Introduction

Post-ST elevation myocardial infarction (STEMI) course can be complicated with mitral regurgitation (MR) which has significant impact on in-patient outcomes and post-discharge course. MR in the setting of STEMI can be due to left ventricular dilatation, papillary muscle rupture or chordal rupture.

Purpose

In this retrospective study, we aimed to evaluate the impact of MR on readmission within one year after percutaneous coronary intervention (PCI) in STEMI patients.

Methods

We conducted a single-center retrospective observation cohort study. We included all patients admitted to the hospital with diagnosis of STEMI, underwent PCI during the same admission (index admission) and discharged alive in the period between Jan 1st, 2016 and Sep 30th, 2018. Factors associated with readmission due to heart failure within 1 year of discharge were evaluated using multivariate logistic regression and results were reported as odds ratio (OR) with p-value <0.05 indicating statistical significance.

Results

A total of 1257 patients were included in our retrospective analysis. The mean age of the study population was 51±10 years. Around 16% (n=206) of the study population had mitral regurgitation (MR) during their admission for STEMI. Among them, 195 patients had newly discovered MR. MR severity was mild in 196 (95%) patients with MR. Unplanned readmission due to cardiac reasons within 1 year of discharge occurred in 103 (8.2%) patients. Among them, 37 (3%) were readmitted due to heart failure. MR was found to increase the likelihood of readmission due to heart failure within one year after PCI among patients with STEMI by three times (aOR=3.13, 95% CI 1.39–7.03; p-value 0.006). As demonstrated in table 1, other positive predictors for readmission due to heart failure were female gender (aOR=3.80, 95% CI 1.22–11.86; p-value 0.021), chronic kidney disease (aOR=4.56, 95% CI 1.22–17.03; p-value 0.024), and clinical heart failure during the index admission (aOR=4.82, 95% CI 1.53–15.15; p-value 0.007). Interestingly, reduced left ventricular ejection fraction was not a significant predictor of heart failure readmission.

Conclusion

Mitral regurgitation is relatively common in STEMI and most frequently presents with mild severity. In our study, MR was found to be a strong predictor for readmission due to heart failure within one year after PCI among patients with STEMI, which may warrant frequent follow-up for these patients and proper initiation of and titration of guideline-directed medical therapy (GDMT).

Funding Acknowledgement

Type of funding sources: None.

The impact of empagliflozin on cardiac physiology and fibrosis early after myocardial infarction in non-diabetic rats

BACKGROUND

Myocardial fibrosis is a multistep process, which results in collagen deposition in the injured muscle. Empagliflozin, a sodium-glucose cotransporter 2 inhibitor (SGLT2i), decreases cardiovascular events risk. Little is known on the effects of empagliflozin in non-diabetic patients early post myocardial infarction.

METHODS

Fourteen non-diabetic rats underwent myocardial infarction induction, and treated or not (control)immediately after myocardial infarction by daily empagliflozin (30 mg/kg/day). We evaluated cardiac function at baseline, 2 and 4 weeks after myocardial infarction by echocardiography, and prior to sacrifice by Millar pressure-volume system. We performed histological and biochemical evaluation of fibrosis and humoral factors promoting fibrosis.

RESULTS

Baseline ejection fractions were 69.9 ± 5.3% and 76.4 ± 5.4%, and dropped to final values of 40.1 ± 5.8% and 39.4 ± 5.4% in the control and empagliflozin groups, respectively (P < 0.001 vs. baseline, P > 0.05 between groups). Collagen deposition, measured as collagen volume fraction, was higher in both the scar and the remote cardiac areas of the control group 79.1 ± 6.2% and 4.6 ± 2.5% for control, and 53.8 ± 5.4% and 2.5 ± 1.3% for empagliflozin group, respectively (P < 0.05 for each). Remote cardiac muscle collagen, measured by hydroxyproline, was 4.1 ± 0.4 μg/μl and 3.6 ± 0.2 μg/μl (P = 0.07). TGF-β1 and Smad3 expression decreased by empagliflozin-18.73 ± 16.32%, 9.16 ± 5.69% and 16.32 ± 5.4%, 7.00 ± 5.28% in the control and empagliflozin groups, respectively (P < 0.05).

CONCLUSION/INTERPRETATION

Empagliflozin administered early after myocardial infarction reduce myocardial fibrosis and inhibit the TGF-β1/Smad3 fibrotic pathway, probably prior to exerting any hemodynamic or physiological effect.

Calibration of MTT assay in proton beams using radiochromic films

PURPOSE

This study provides methodology of calibrating as well as controlling the output for an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) colorimetric assay irradiated in a low energy proton beam using EBT3-model GAFCHROMIC^TM film, without correcting for quenching effect.

METHODS

A calibrated Markus ionization chamber was used to measure the depth dose and beam output for 26.5 MeV protons produced by a CS30 cyclotron. A time-controlled aluminum cylinder was added in front of the horizontal beam-exit serving as a radiation shutter. Following the TRS-398 reference dosimetry protocol for proton beams, the output was calibrated in water at a reference depth of 3 mm. EBT3 film was calibrated for doses up to 8 Gy at the same depth. To verify the dose distribution for each 96-well MTT assay plate, EBT3 film was placed at the reference depth during irradiation and cell doses were scaled by measured percent depth dose (PDD) data.

RESULTS

The radiochromic film dosimetry system in this study provides dose measurements with an uncertainty better than 3.3% for doses higher than 1 Gy. From a single exposure and utilizing the Gaussian shape of the beam, multiple dose points can be obtained within different wells of the same plate ranging from 6.9 Gy (sigma ∼4%) in the central well, and 2 Gy (sigma ∼8%) for wells positioned closer to the periphery.

CONCLUSIONS

We described a methodology for radiochromic film-based dose monitoring system, using low-energy protons, which can be used for the MTT assay in any proton beam, except within Bragg peak region.

Analysis and purification of phorbol esters using normal phase HPLC and photodiode-array detection

For the first time a normal-phase HPLC method using photodiode-array detection is described for the analysis and purification of phorbol esters. The use of the method is demonstrated with examples of 10 different tigliane and daphnane esters (TPA, DOPP, DOPPA, Sap A, Sap B, Sap C, Sap D, Thy A, Ro and Rx). Both analytical and semipreparative techniques were developed. The method has been used in the final purification of DOPP and Rx from plant extracts. The method can be employed in the areas of phytochemistry, biochemistry and pharmacology/toxicology, where small samples of the toxic materials are required for research.