Project description:IntroductionPrevention of the no-reflow phenomenon has a crucial role in primary percutaneous coronary intervention (P-PCI) procedures.AimTo assess the effects of early intracoronary administration of nicorandil (NIC) during P-PCI on myocardial microcirculation in patients with acute myocardial infarction (AMI).Material and methodsA total of 120 patients with first acute anterior wall ST segment elevation myocardial infarction who underwent P-PCI were randomly divided into two groups: the NIC group (A, n = 60) and the placebo group (B, n = 60). Before stent placement, NIC or normal saline was injected using a guiding catheter. The thrombolysis in myocardial infarction (TIMI) grade, TIMI myocardial perfusion grade (TMPG), resolution of ST segment elevation (defined as > 50% decrease in ST elevation) 1 h after surgery, and 99Tcm-methoxyisobutyl isocyanide (MIBI) rest myocardial perfusion imaging (MPI) via single-photon emission computed tomography (99Tcm-MIBI SPECT) findings 10 days after surgery were compared between the two groups.ResultsThe number of patients who achieved TIMI grade 3 (96.67% vs. 86.67%; p = 0.047) and TMPG 3 (95% vs. 83.33%; p = 0.040) was higher in the NIC group than in the placebo group. Resolution of ST segment elevation occurred in 95% and 81.67% of the patients in the NIC and placebo groups, respectively (p = 0.023); the MPI score of the two groups was 4.1 ±1.89 and 7.3 ±2.65, respectively (p = 0.014).ConclusionsEarly coronary administration of NIC can significantly reduce the damage in the myocardial microcirculation caused by P-PCI and the myocardial infarct size in patients with AMI.
Project description:Mortality risk of ST-segment elevation myocardial infarction (STEMI) patients shows high variability. In order to assess individual risk, a number of scoring systems have been developed and validated. Yet, as treatment approaches evolve over time with improving outcomes, there is a need to build new risk prediction algorithms to maintain/increase prognostic accuracy. One of the most relevant improvements of therapy is primary percutaneous coronary intervention (PCI). We overview the characteristics and discriminative performance of the most studied and some recently constructed mortality risk models that were validated in patients with STEMI who underwent primary PCI.
Project description:BackgroundImplementation of the first Danish helicopter emergency medical service (HEMS) was associated with reduced time from first medical contact to treatment at a specialized centre for patients with suspected ST elevation myocardial infarction (STEMI). We aimed to investigate effects of HEMS on mortality and labour market affiliation in patients admitted for primary percutaneous coronary intervention (PCI).MethodsIn this prospective observational study, we included patients with suspected STEMI within the region covered by the HEMS from January 1, 2010, to April 30, 2013, transported by either HEMS or ground emergency medical services (GEMS) to the regional PCI centre. The primary outcome was 30-day mortality.ResultsAmong the 384 HEMS and 1220 GEMS patients, time from diagnostic ECG to PCI centre arrival was lower with HEMS (median 71 min vs. 78 min with GEMS; P = 0.004). Thirty-day mortality was 5.0% and 6.2%, respectively (adjusted OR = 0.82, 95% CI 0.44-1.51, P = 0.52. Involuntary early retirement rates were 0.62 (HEMS) and 0.94 (GEMS) per 100 PYR (adjusted IRR = 0.68, 0.15-3.23, P = 0.63). The proportion of patients on social transfer payments longer than half of the follow-up time was 22.1% (HEMS) vs. 21.2% (adjusted OR = 1.10, 0.64-1.90, P = 0.73).ConclusionIn an observational study of patients with suspected STEMI in eastern Denmark, no significant beneficial effect of helicopter transport could be detected on mortality, premature labour market exit or work ability. Only a study with random allocation to one system vs. another, along with a large sample size, will allow determination of superiority of helicopter transport.
Project description:BackgroundAlthough risk adjustment remains a cornerstone for comparing outcomes across hospitals, optimal strategies continue to evolve in the presence of many confounders. We compared conventional regression-based model to approaches particularly suited to leveraging big data.Methods and resultsWe assessed hospital all-cause 30-day excess mortality risk among 8952 adults undergoing percutaneous coronary intervention between October 1, 2011, and September 30, 2012, in 24 Massachusetts hospitals using clinical registry data linked with billing data. We compared conventional logistic regression models with augmented inverse probability weighted estimators and targeted maximum likelihood estimators to generate more efficient and unbiased estimates of hospital effects. We also compared a clinically informed and a machine-learning approach to confounder selection, using elastic net penalized regression in the latter case. Hospital excess risk estimates range from -1.4% to 2.0% across methods and confounder sets. Some hospitals were consistently classified as low or as high excess mortality outliers; others changed classification depending on the method and confounder set used. Switching from the clinically selected list of 11 confounders to a full set of 225 confounders increased the estimation uncertainty by an average of 62% across methods as measured by confidence interval length. Agreement among methods ranged from fair, with a κ statistic of 0.39 (SE: 0.16), to perfect, with a κ of 1 (SE: 0.0).ConclusionsModern causal inference techniques should be more frequently adopted to leverage big data while minimizing bias in hospital performance assessments.
Project description:It has been previously demonstrated that ticagrelor can reduce mortality compared to clopidogrel in acute coronary syndrome (ACS) patients. However, the mechanism for this mortality reduction remains uncertain. The objective of the present study is to assess the impact of chronic ticagrelor treatment on microvascular circulation. A total of 120 participants aged 20-85 years with clinical diagnosis of ACS will be randomized in a 1:1 fashion to the following two groups: ticagrelor 90 mg twice daily; clopidogrel 75 mg once daily. To evaluate the status of microcirculation, the primary end point is coronary microvascular dysfunction measured using an index of microcirculatory resistance (IMR) at 6 months after receiving the study agent. The purpose of this trial is to investigate whether ticagrelor, beyond its antiplatelet efficacy, could improve coronary microcirculation more effectively than clopidogrel for patients with ACS.
Project description:BackgroundPrevious studies have demonstrated the feasibility of primary percutaneous coronary intervention (PPCI) in carefully selected nonagenarians. Although current guidelines recommend immediate revascularization in patients with ST elevation myocardial infarction (STEMI) it remains unclear whether PPCI reduces mortality in nonagenarians. The objective of this study is to compare mortality in nonagenarians presenting via the PPCI pathway who undergo coronary intervention, versus those who are managed medically.Methods and resultsA total of 111 consecutive nonagenarians who presented to our tertiary center via the PPCI pathway between July 2013 and December 2018 with myocardial infarction were included. Clinical and angiographic details were collected alongside data on all-cause mortality. The final diagnosis was STEMI in 98 (88.3%) and NSTEMI in 13 (11.7%). PPCI was performed in 42 (37.8%), while 69 (62.2%) were medically managed. A significant number of the medically managed cohort had atrial fibrillation (23.2% vs 2.4% p = 0.003) and presented with a completed infarct (43.5% vs 4.8% p = 0.001). Other baseline and clinical variables were well matched in both groups. There was a trend towards increased 30-day mortality in the medically managed group (40.6% vs 23.8% p = 0.07). Kaplan Meier survival analysis demonstrated a significant difference in survival by 3 years (48.1% vs 21.7% p = 0.01). This was the case even when those with completed infarcts were excluded (44.3% vs 14.6%, p = 0.01).ConclusionIn this series of selected nonagenarians presenting with acute myocardial infarction, those undergoing PPCI appeared to have a lower mortality compared to those managed medically.
Project description:Ischemic heart disease (IHD) affects more than 20 million adults in the United States. Although classically attributed to atherosclerosis of the epicardial coronary arteries, nearly half of patients with stable angina and IHD who undergo invasive coronary angiography do not have obstructive epicardial coronary artery disease. Ischemia with nonobstructive coronary arteries is frequently caused by microvascular angina with underlying coronary microvascular dysfunction (CMD). Greater understanding the pathophysiology, diagnosis, and treatment of CMD holds promise to improve clinical outcomes of patients with ischemic heart disease.
Project description:Reperfusion may cause intramyocardial hemorrhage (IMH) by extravasation of erythrocytes through severely damaged endothelial walls. The purpose of the study was to evaluate the clinical significance of IMH in relation to infarct size, microvascular obstruction (MVO) and function in patients after primary percutaneous intervention. Forty-five patients underwent cardiovascular MR imaging (CMR) 1 week and 4 months after primary stenting for a first acute myocardial infarction. T2-weighted spin-echo imaging (T2W) was used to assess infarct related edema and IMH, and delayed enhancement (DE) was used to assess infarct size and MVO. Cine CMR was used to assess left ventricular volumes and function at baseline and at 4 months follow-up. In 22 (49%) patients, IMH was detected as areas of attenuated signal in the core of the high signal intensity region on T2W images. Patients with IMH had larger infarcts, higher left ventricular volumes and lower ejection fraction. Contrast-to-noise ratio (CNR) between hyperintense periphery and the hypo-intense core of the T2W ischemic area correlated to peak CKMB, total infarct size and MVO size. Using univariable analysis, CNR predicted ejection fraction at baseline (beta = -0.62, P = 0.003) and follow-up (beta = -0.84, P < 0.001). However, after multivariable analysis, baseline ejection fraction and presence of MVO were the only parameters that predicted functional changes at follow-up. IMH was found in the majority of patients with MVO after reperfused myocardial infarction. It was closely related to markers of infarct size, MVO and function, but did not have prognostic significance beyond MVO.
Project description:We studied new microRNAs involved in the left ventricular adverse remodeling (LVAR) process after the ST elevation myocardial infarction (STEMI). We analyzed the expression of miRNAs in peripheral blood mononuclear cells (PBMCs) isolated from a group of non-LVAR (n = 5) and LVAR STEMI patients (n = 5), before (0 hour) and after a primary percutaneous coronary intervention (PPCI; 6 hours).