Risk Of Subsequent Clinical Events Research Articles

Impact of morphofunctional assessment with quantitative flow ratio and optical coherence tomography in patients with acute coronary syndromes.

Combining morphological and physiological evaluations might improve the risk stratification of patients who undergo percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS) culprit lesions. We aimed to investigate the clinical utility of morphofunctional evaluation after PCI for identifying ACS patients with increased risk of subsequent clinical events. We retrospectively studied 298 consecutive ACS patients who had undergone optical coherence tomography (OCT)-guided PCI. We performed OCT-based morphological analysis and quantitative flow ratio (QFR)-based physiological assessment immediately after PCI. The non-culprit segment (NCS) was defined as the most stenotic untreated segment in the culprit vessel. The primary outcome was target vessel failure (TVF), a composite of cardiac death, target vessel-related myocardial infarction, and ischaemia-driven target vessel revascularisation. During a median follow-up period of 990 days, 42 patients experienced TVF. Cox regression analysis revealed that the presence of thin-cap fibroatheroma (TCFA) in the NCS and a low post-PCI QFR, or the presence of TCFA in the NCS and a high ΔQFR in the NCS (QFRNCS), were independently associated with TVF. The subgroup with TCFA in the NCS and a low post-PCI QFR had a significantly higher incidence of TVF (75%) than the other subgroups, and those with TCFA in the NCS and a high ΔQFRNCS had a significantly higher incidence of TVF (86%) than the other subgroups. The integration of TCFA in NCS, post-PCI QFR, and ΔQFRNCS with traditional risk factors significantly enhanced the identification of subsequent TVF cases. Combining post-PCI OCT and QFR evaluation may enhance risk stratification for ACS patients after successful PCI, particularly in predicting subsequent TVF.

Heart Failure in Cardiac Rehabilitation: A REVIEW AND PRACTICAL CONSIDERATIONS.

Exercise cardiac rehabilitation (CR) represents an evidence-based therapy for patients with heart failure with reduced ejection fraction (HFrEF) and this article provides a concise review of the relevant exercise testing and CR literature, including aspects unique to their care. A hallmark feature of HFrEF is exercise intolerance (eg, early-onset fatigue). Drug therapies for HFrEF target neurohormonal pathways to blunt negative remodeling of the cardiac architecture and restore favorable loading conditions. Guideline drug therapy includes β-adrenergic blocking agents; blockade of the renin-angiotensin system; aldosterone antagonism; sodium-glucose cotransport inhibition; and diuretics, as needed. Various assessments are used to quantify exercise capacity in patients with HFrEF, including peak oxygen uptake measured during an exercise test and 6-min walk distance. The mechanisms responsible for the exercise intolerance include abnormalities in ( a ) central transport (chronotropic response, stroke volume) and ( b ) the diffusion/utilization of oxygen in skeletal muscles. Cardiac rehabilitation improves exercise capacity, intermediate physiologic measures (eg, endothelial function and sympathetic nervous system activity), health-related quality of life (HRQoL), and likely clinical outcomes. The prescription of exercise in patients with HFrEF is generally similar to that for other patients with cardiovascular disease; however, patients having undergone an advanced surgical therapy do present with features that require attention. Few patients with HFrEF enroll in CR and as such, many miss the derived benefits, including improved exercise capacity, a likely reduction in risk for subsequent clinical events (eg, rehospitalization), improved HRQoL, and adoption of disease management strategies.

Progression of myocardial fibrosis in hypertrophic cardiomyopathy: mechanisms and clinical implications.

AimsMyocardial fibrosis as detected by late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) is a powerful prognostic marker in hypertrophic cardiomyopathy (HCM) and may be progressive. The precise mechanisms underlying fibrosis progression are unclear. We sought to assess the extent of LGE progression in HCM and explore potential causal mechanisms and clinical implications.Methods and resultsSeventy-two HCM patients had two CMR (CMR1-CMR2) at an interval of 5.7 ± 2.8 years with annual clinical follow-up for 6.3 ± 3.6 years from CMR1. A combined endpoint of heart failure progression, cardiac hospitalization, and new onset ventricular tachycardia was assessed. Cine and LGE imaging were performed to assess left ventricular (LV) mass, function, and fibrosis on serial CMR. Stress perfusion imaging and cardiac energetics were undertaken in 38 patients on baseline CMR (CMR1). LGE mass increased from median 4.98 g [interquartile range (IQR) 0.97–13.48 g] to 6.30 g (IQR 1.38–17.51 g) from CMR1 to CMR2. Substantial LGE progression (ΔLGE ≥ 4.75 g) occurred in 26% of patients. LGE increment was significantly higher in those with impaired myocardial perfusion reserve (<MPRI 1.40) and energetics (phosphocreatine/adenosine triphosphate <1.44) on baseline CMR (P ≤ 0.01 for both). Substantial LGE progression was associated with LV thinning, increased cavity size and reduced systolic function, and conferred a five-fold increased risk of subsequent clinical events (hazard ratio 5.04, 95% confidence interval 1.85–13.79; P = 0.002).ConclusionMyocardial fibrosis is progressive in some HCM patients. Impaired energetics and perfusion abnormalities are possible mechanistic drivers of the fibrotic process. Fibrosis progression is associated with adverse cardiac remodelling and predicts an increased risk of subsequent clinical events in HCM.

Rational and design of the European randomized Optical Coherence Tomography Optimized Bifurcation Event Reduction Trial (OCTOBER)

Percutaneous coronary intervention in complex bifurcation lesions is prone to suboptimal implantation results and is associated with increased risk of subsequent clinical events. Angiographic ambiguity is high during bifurcation stenting, but it is unknown if procedural guidance by intravascular optical coherence tomography (OCT) improves clinical outcome. OCTOBER is a randomized, investigator-initiated, multicenter trial aimed to show superiority of OCT-guided stent implantation compared to standard angiographic-guided implantation in bifurcation lesions. The primary outcome measure is a 2-year composite end point of cardiac death, target lesion myocardial infarction, and ischemia-driven target lesion revascularization. The calculated sample size is 1,200 patients in total, and allocation is 1:1. Eligible patients have stable or unstable angina pectoris or stabilized non–ST elevation myocardial infarction, and a coronary bifurcation lesion with significant main vessel stenosis and more than 50 % stenosis in a side branch with a reference diameter ≥2.5mm. Treatment is performed by the provisional side branch stenting technique or 2-stent techniques, and the systematic OCT guiding protocol is aimed to evaluate (1) plaque preparation, (2) lesion length, (3) segmental reference sizes, (4) lesion coverage, (5) stent expansion, (6) malapposition, (7) wire positions, and (8) ostial results. A positive outcome of the OCTOBER trial may establish OCT as a routine tool for optimization of complex percutaneous coronary intervention, whereas a negative result would indicate that OCT remains a tool for ad hoc evaluation in selected cases.

Prevalence of Extracoronary Vascular Abnormalities and Fibromuscular Dysplasia in Patients With Spontaneous Coronary Artery Dissection

Spontaneous coronary artery dissection (SCAD) is a cause of acute coronary syndrome, often occurring in young women. The utility of comprehensive imaging and clinical significance of detected vascular abnormalities have yet to be determined. We hypothesized that extracoronary vascular abnormalities (EVAs) are common in SCAD and aimed to study the prevalence and distribution of these findings. We enrolled 115 patients with confirmed SCAD who were evaluated at the Mayo Clinic SCAD Clinic from February 2010 to May 2014 and prospectively underwent comprehensive computed tomography angiography imaging of the neck, chest, abdomen, and pelvis (SCAD computed tomography angiography protocol, n=95) or had retrospective review of outside studies (n= 20) including head imaging (n=40). Follow-up was determined by last clinical visit or study correspondence and included review of recurrent SCAD or myocardial infarction, congestive heart failure, and death. We reported EVAs in 66% of patients with SCAD, most frequently in the abdomen (36%), pelvis (28%), and neck (27%). Only 1 patient had EVA in the chest (aortic dissection and Marfan's). Fibromuscular dysplasia (FMD) (exclusively multifocal) was the most common type of EVA (45%). Vascular abnormalities in those with head imaging included intracranial aneurysms (n = 9) and FMD (n = 3). There were no deaths at median follow-up of 21months (Q1 to Q3 7.7 to 55). The presence of FMD was not associated with SCAD recurrence (relative risk [RR] 1.2; confidence interval [95% CI] 0.60, 2.5), congestive heart failure (RR 0.66; 95% CI 0.20, 2.3), or myocardial infarction (RR 1.34; 95% CI 0.69, 2.6). In conclusion, EVAs including FMD, dissections, aneurysms, and dilation are common in patients with SCAD and occur in a wide anatomic distribution. The presence of EVAs and/or FMD did not correlate with the risk of subsequent clinical events, but future studies with increased power and longer follow-up will be important to further assess the role of EVAs in patients with SCAD.

Anticoagulant therapy and outcomes in patients with prior or acute heart failure and acute coronary syndromes: Insights from the APixaban for PRevention of Acute ISchemic Events 2 trial

Clinical outcomes and the effects of oral anticoagulants among patients with acute coronary syndrome (ACS) and either a history of or acute heart failure (HF) are largely unknown. We aimed to assess the relationship between prior HF or acute HF complicating an index ACS event and subsequent clinical outcomes and the efficacy and safety of apixaban compared with placebo in these populations. High-risk patients were randomly assigned post-ACS to apixaban 5.0 mg or placebo twice daily. Median follow-up was 8 (4-12) months. The primary outcome was cardiovascular death, myocardial infarction, or stroke. The main safety outcome was thrombolysis in myocardial infarction major bleeding. Heart failure was reported in 2,995 patients (41%), either as prior HF (2,076 [28%]) or acute HF (2,028 [27%]). Patients with HF had a very high baseline risk and were more often managed medically. Heart failure was associated with a higher rate of the primary outcome (prior HF: adjusted hazard ratio [HR] 1.73, 95% CI 1.42-2.10, P < .0001, acute HF: adjusted HR 1.65, 95% CI 1.35-2.01, P < .0001) and cardiovascular death (prior HF: HR 2.54, 95% CI 1.82-3.54, acute HF: adjusted HR 2.52, 95% CI 1.82-3.50). Patients with acute HF also had significantly higher rates of thrombolysis in myocardial infarction major bleeding (prior HF: adjusted HR 1.22, 95% CI 0.65-2.27, P = .54, acute HF: adjusted HR 1.78, 95% CI 1.03-3.08, P = .04). There was no statistical evidence of a differential effect of apixaban on clinical events or bleeding in patients with or without prior HF; however, among patients with acute HF, there were numerically fewer events with apixaban than placebo (14.8 vs 19.3, HR 0.76, 95% CI 0.57-1.01, interaction P = .13), a trend that was not seen in patients with prior HF or no HF. In high-risk patients post-ACS, both prior and acute HFs are associated with an increased risk of subsequent clinical events. Apixaban did not significantly reduce clinical events and increased bleeding in patients with and without HF; however, there was a tendency toward fewer clinical events with apixaban in patients with acute HF.

Nonfatal myocardial infarction and long-term outcomes in coronary artery disease

Therapies may reduce short-term rates of nonfatal myocardial infarction (MI) without a detectable effect on mortality. We sought to estimate the long-term clinical implications of nonfatal MI occurring within the first 3 and 6 months after initial cardiac catheterization. We included consecutive patients with significant coronary artery disease (≥75% stenosis in ≥1 epicardial segments) undergoing diagnostic catheterization between January 1, 1999, and September 30, 2006. Landmark analyses were performed for patients surviving at 3- and 6-month follow-up. At these times, patients were divided into groups based upon occurrence of a nonfatal MI subsequent to catheterization. Among 14,890 patients alive at 3 months (669 with MI and 14,221 without an MI), having an MI during the initial 3-month period was a significant predictor of reduced 4-year survival (77.1% vs 83.5%, hazard ratio 1.40, 95% CI 1.21-1.63, P < .001), survival free of MI (68.4% vs 78.5%, hazard ratio 1.50, 95% CI 1.32-1.71, P < .001), and survival free of MI or revascularization (59.7% vs 68.5%, hazard ratio 1.34, 95% CI 1.19-1.51, P < .001). Adjusted hazard ratios were similar for patients surviving to 6 months (804 with MI and 13,842 without an MI). Nonfatal MIs occurring within the first 3 and 6 months after diagnostic catheterization are associated with a significant increase in the risk for subsequent clinical events. Clinical studies with limited follow-up periods may underestimate the long-term value of therapies that reduce early MI rates as downstream benefits continue to accrue over time.

Evolution of Spontaneous Atherosclerotic Plaque Rupture With Medical Therapy

Ruptured coronary atheromatous plaque is generally considered to involve a high risk of subsequent clinical events. Few data are available on the natural evolution of non-culprit-lesion ruptured plaque. We therefore used serial intravascular ultrasound (IVUS) to study how such lesions, detected in the context of a first acute coronary syndrome with elevated troponin I levels, develop. Fourteen patients with 28 distinct plaque ruptures (2+/-1 per patient) without significant associated stenosis (minimal lumen cross-sectional area >4 mm2) were included and systematically treated with 40 mg statin and antiplatelet agent (clopidogrel and aspirin for > or =9 months). Mean clinical and IVUS follow-up was 22+/-13 months (median, 22 months). No clinical event related to the lesion under study occurred. On final IVUS examination, half (14 of 28) of the ruptured plaques had healed, and the degree of stenosis tended to diminish (stenosis, 22+/-17% versus 29+/-17% at baseline; P=0.056). No healing-prediction criterion could be identified. Nearly 2 years of follow-up found that spontaneous coronary atheromatous plaque rupture without significant stenosis detected on first acute coronary syndrome healed without significant plaque modification in 50% of cases with medical therapy.

Prospective Comparison of Patient Characteristics and Outcome of Non-prior Aspirin Users versus Aspirin Users with Unstable Angina or Non-Q-Wave Myocardial Infarction Treated with Combination Antithrombotic Therapy.

The objective of this study was to determine if aspirin users presenting with acute coronary syndromes are at higher risk for subsequent clinical events. In a trial evaluating combination antithrombotic therapy in resting angina or non-Q-wave myocardial infarction (MI), patients were prospectively dichotomized on admission into nonprior versus recent aspirin users. Then 105 nonprior users and 144 users were randomized to treatment with aspirin plus heparin/warfarin for 12 weeks. Recurrent myocardial ischemia occurring during the 12-week follow-up period was defined as recurrent angina (with electrocardiographic changes or prompting coronary revascularization), MI, or death. Prior aspirin users had a significantly higher incidence of previous MI, prior bypass grafting, beta-blocker use, or hypertension (p </= 0.003) and were more likely to present with unstable angina as opposed to non-Q-wave MI. (p </= 0.008). The cumulative probability of recurrent ischemic endpoints for nonprior versus recent users was 10% versus 21% at 14 days (log rank p = 0.03), and 19% versus 29%, at 12 weeks (p = 0.06). Using the Cox model, adjusting for variables significantly associated with outcome, aspirin use remained a significant predictor of 14-day outcome (p = 0.04) but not of 12-week outcome (p = 0.06). In conclusion, even after adjusting for significant differences in baseline variables, aspirin users presenting with rest angina or non-Q-infarction have a worse short-term prognosis in spite of maximal medical therapy.

Clinical and angiographic characteristics and outcome of patients with rest-unstable angina occurring during regular aspirin use

Today many patients admitted with an acute coronary syndrome are already taking aspirin. Because they have symptoms despite antithrombotic therapy, these patients are presumed to be at higher risk for subsequent clinical events. In a pilot trial of antithrombotic therapy in patients with unstable angina at rest or non-Q wave infarction, 93 patients admitted within 48 h of pain were prospectively followed up for 12 weeks. On admission, 29 patients (31%) were already taking daily aspirin; 64 (68%) were receiving no antiplatelet agent. After enrollment all patients received antithrombotic therapy with either aspirin or heparin according to protocol regardless of prior aspirin use.The two groups (prior users versus nonusers of aspirin) were similar with regard to age, gender, coronary risk factors, prior antianginal medication, duration of symptomatic coronary disease, presentation with non-Q wave infarction and extent of electrocardiographic changes on admission. Quantitative analysis of coronary arteriograms (on a 0 to 10 scale) showed similar myocardium-in-jeopardy scores (JS). Follow-up events (recurrent ischemia [Isch], infarction [MI] and revascularization [Revasc]) were: Prior Aspirin UseIschMIRevascJSYes27%3%44%3.7%No33%5%51%3.9%Aspirin users experiencing rest angina are similar to other patients with ischemic rest pain. The “resistant to aspirin” group Joes not constitute a subgroup that is at higher risk for cardiac events or revascularization.