Background In patients with ST-elevation myocardial infarction (STEMI), coronary microcirculatory dysfunction (CMD) may predict the risk of heart failure and mortality, and can be assessed by the index of microcirculatory resistance (IMR) and the more novel index, microvascular resistance reserve (MRR). We investigated MRR measurements and its relationship with left ventricular function changes assessed by cardiac magnetic resonance (CMR). Methods In 26 patients with STEMI and single-vessel disease treated with primary percutaneous coronary intervention (PPCI), invasive flow- and pressure measurements were performed after PPCI and repeated after 3 months. CMR was performed within 72 h of PPCI and after 3 months. CMD was defined as MRR ≤ 3 and patients were divided into two groups: MRR ≤ 3 and MRR > 3, as well as into IMR ≥ 40 and IMR < 40. Six years clinical follow-up was conducted in all patients. Results Median MRR after PPCI was 2.6 [Interquartile range (IQR) 1.5, 4.0] and 15 patients (58 %) had a MRR ≤ 3, while median IMR was 33 [IQR 13, 79]. Patients with MRR ≤ 3 had significantly greater infarct size (IS) at both index (IS(late gadolinium enhancement (LGE)): median 1796 [IQR 827, 4167] vs 788 [IQR 308, 1201], p = 0.024) and at 3-month follow-up (IS(LGE): median 928 [IQR 566, 2024] vs 232 [IQR 82, 807], p = 0.027) compared to patients with MRR > 3. Assessing the CMD with IMR, IS did not differ significantly, neither at baseline (IMR ≥ 40 IS(LGE) median: 1483 [IQR 827, 4167] vs IMR < 40,870 [IQR 310, 2000], p = 0.21) nor at 3-month follow-up (IS(LGE): median 824 [IQR 587, 1850] vs 566 [IQR 107, 834], p = 0.22). After six years, two patients died (one cardiac cause), and one patient was hospitalized for heart failure, all patients had MRR ≤ 3. Conclusions In this small pilot study, patients with STEMI and MRR ≤ 3 had significantly greater IS after PPCI and after 3 months compared to patients with MRR > 3, while IS did not differ in IMR groups.

Background Cardiac 15 O-water PET is a noninvasive method to evaluate epicardial and microvascular dysfunction and further quantitate absolute myocardial blood flow (MBF). Aim: The aim of this study was to assess the impact of revascularization on MBF and myocardial flow reserve (MFR) assessed with 15 O-water PET and invasive flow and pressure measurements. Methods In 21 patients with single-vessel disease referred for percutaneous coronary intervention (PCI), serial PET perfusion imaging and fractional flow reserve (FFR), coronary flow reserve (CFR) and index of microcirculatory resistance (IMR) were performed during PCI and after 3 months. Results In the affected myocardium, stress MBF and MFR increased significantly from before revascularization to 3 months after revascularization: stress MBF 2.4 ± 0.8 vs. 3.2 ± 0.8; P < 0.001 and MFR 2.5 ± 0.8 vs. 3.4 ± 1.1; P = 0.004. FFR and CFR increased significantly from baseline to after revascularization and remained stable from after revascularization to 3-month follow-up: FFR 0.64 ± 0.20 vs. 0.91 ± 0.06 vs. 0.91 ± 0.07; P < 0.001; CFR 2.4 ± 1.2 vs. 3.6 ± 1.9 vs. 3.6 ± 1.9; P < 0.001, whereas IMR did not change significantly: 30.3 ± 22.9 vs. 30.1 ± 25.3 vs. 31.9 ± 25.2; P = ns. After revascularization, an increase in stress MBF was associated with an increase in FFR ( r = 0.732; P < 0.001) and an increase in MFR ( r = 0.499; P = 0.021). IMR measured before PCI was inversely associated with improvement in stress MBF, ( r = −0.616; P = 0.004). Conclusion Recovery of myocardial perfusion after PCI was associated with an increase in FFR 3 months after revascularization. Microcirculatory dysfunction was associated with less improvement in myocardial perfusion.

The diagnostic accuracy of non-invasive diagnostic methods for detecting coronary artery disease has increased in recent years. This study aimed to assess the diagnostic performance of 15O-water positron emission tomography (PET) in terms of stress myocardial blood flow (MBF) and myocardial flow reserve (MFR) in patients with single-vessel disease referred for percutaneous coronary intervention (PCI), using fractional flow reserve (FFR) value of ≤0.80 as the reference for a significant stenosis. We also assessed the influence of the index of microcirculatory resistance (IMR) on the diagnostic performance of PET. 15O-water PET FFR and IMR were measured before PCI in 26 patients with single-vessel disease. Stress MBF < 2.5 ml/min/g (95% confidence interval [CI]) had sensitivity 78% (95% CI: 52%–94%), specificity 50% (95% CI: 16%–84%), positive predictive value (PPV) 78% (95% CI: 63%–88%), negative predictive value (NPV) 50% (95% CI: 25%–75%), and accuracy 69% (95% CI: 48%–86%). MFR < 2.5 had sensitivity 72% (95% CI: 47%–90%), specificity 75% (95% CI: 35%–97%), PPV 87% (95% CI: 65%–96%), NPV 55% (95% CI: 34%–74%), and accuracy 73% (95% CI: 52%–88%). In patients with IMR > 24, stress MBF correlated with FFR (r = 0.651; p = 0.016) whereas stress MBF did not correlate with FFR in patients with IMR < 24. In conclusion, stress MBF and MFR had modest diagnostic performance compared to invasive FFR measurements in patients with single-vessel disease.

Aims:The aim of the study was to evaluate the incidence and causes of rehospitalisation within one year after percutaneous coronary intervention (PCI) in a country where the National Health Service provides universal tax-supported healthcare, guaranteeing residents free hospital access.Methods and results: Between January 2010 and September 2014, 17,111 patients were treated with PCI in two University Hospitals in Western Denmark.Patients who were readmitted within one year after PCI were identified.The overall one-year readmission rate was 50.4%.The cause was angina/myocardial infarction (MI) in 4,282 patients (49.7%), and other reasons in 4,334 (50.3%).Predictors of angina/MI-related readmissions were female gender (odds ratio [OR] 1.15, 95% confidence interval [CI]: 1.07-1.25),diabetes (OR 1.14, 95% CI: 1.04-1.26),age (per 10-year increase) (OR 0.86, 95% CI: 0.83-0.88),and indication for index PCI (stable angina pectoris as reference): ST-segment elevation myocardial infarction (OR 1.34, 95% CI: 1.23-1.47)and non-ST-segment elevation myocardial infarction (OR 1.18, 95% CI: 1.08-1.29).Predictors for other readmissions were female gender (OR 1.09, 95% CI: 1.01-1.18),diabetes (OR 1.29, 95% CI: 1.18-1.42),age (OR 1.30, 95% CI: 1.26-1.34)and Charlson comorbidity index ≥3 (OR 3.03, 95% CI: 2.71-3.27). Conclusions:In an unselected patient cohort treated with PCI, half of the patients were rehospitalised within one year, highlighting the impact of comorbidity in patients with ischaemic heart disease.

INTRODUCTION:Reducing hands-off time during cardiopulmonary resuscitation (CPR) is believed to increase survival after cardiac arrests because of the sustaining of organ perfusion. The aim of our study was to investigate whether charging the defibrillator before rhythm analyses and shock delivery significantly reduced hands-off time compared with the European Resuscitation Council (ERC) 2010 CPR guideline algorithm in full-scale cardiac arrest scenarios.METHODS:The study was designed as a full-scale cardiac arrest simulation study including administration of drugs. Participants were randomized into using the Stop-Only-While-Shocking (SOWS) algorithm or the ERC2010 algorithm. In SOWS, chest compressions were only interrupted for a post-charging rhythm analysis and immediate shock delivery. A Resusci Anne HLR-D manikin and a LIFEPACK 20 defibrillator were used. The manikin recorded time and chest compressions.RESULTS:Sample size was calculated with an α of 0.05 and 80% power showed that we should test four scenarios with each algorithm. Twenty-nine physicians participated in 11 scenarios. Hands-off time was significantly reduced 17% using the SOWS algorithm compared with ERC2010 [22.1% (SD 2.3) hands-off time vs. 26.6% (SD 4.8); P<0.05].CONCLUSION:In full-scale cardiac arrest simulations, a minor change consisting of charging the defibrillator before rhythm check reduces hands-off time by 17% compared with ERC2010 guidelines.

OBJECTIVES:(1) To establish the prevalence of incidental extra-cardiac findings (ECFs) in coronary multi detector computed tomography (CCT) performed in a large, homogeneous cohort of patients suspected of coronary artery disease (CAD). (2) To examine whether any association can be established between ECFs and pretest risk as determined by conventional risk factors for CAD, the Diamond-Forrester risk model or coronary artery calcium scores. (3) To assess cost related to extra-cardiac examinations.DESIGN:Retrospective study of consecutive patients who had CCT performed. A large field of view was recreated from the non-enhanced CT scan and evaluated by a radiologist for incidental ECFs.SUBJECTS:Patients with chest pain referred to CTA by a cardiologist.RESULTS:In 1383 patients a total of 481 ECFs were indentified, 378 minor (meaning no follow-up was needed) and 103 major ECFs (ECF followed up clinically and/or with additional imaging), in a total of 393 (28%) patients. 85 (6%) patients had one major ECF and 9 (0.7%) patients had two major ECFs. In 19 (4 cases of malignancy) patients the major ECF had therapeutic consequences. Significant positive associations were found between age and smoking, respectively and the presence of ECFs. The cost estimate of saving one life from malignant disease based on ECF examinations is 40,190€.CONCLUSION:Incidental extra-cardiac findings are common, sometimes revealing serious, even malignant disease. Diagnostic follow-up of major ECFs seems to be cost-effective in a Danish clinical setting. We recommend investigating a large field of view for incidental ECFs following CCT.