Reducing Psychosocial Stress: A Novel Mechanism of Improving Survival from Exercise Training

Background

Exercise training reduces mortality in patients with coronary artery disease. Behavioral characteristics, including depression, hostility, and overall psychosocial stress, have been shown to be independent risk factors for recurrent myocardial infarction and death in these patients. Exercise training can reduce these high-risk behaviors, but it remains uncertain as to what extent the health benefits of exercise training can be attributed to improving these behaviors.

Methods

We evaluated the impact of exercise training during cardiac rehabilitation on mortality in 53 patients with coronary artery disease with high levels of psychosocial stress and in 469 patients with coronary artery disease with low levels of psychosocial stress and compared them with 27 control patients with high psychosocial stress who did not undergo formal cardiac rehabilitation and exercise training.

Results

Mortality was approximately 4-fold greater in patients with high psychosocial stress than in those with low psychosocial stress (22% vs 5%; P = .003). Exercise training decreased the prevalence of psychosocial stress from 10% to 4% (P < .0001) and similarly improved peak oxygen uptake in patients with high and low psychosocial stress. Mortality in patients who improved exercise capacity by ≥ 10% (high exercise change) was 60% lower than in patients who had < 10% improvement in exercise capacity (low exercise change) (P = .009). Mortality was lower in patients with high psychosocial stress with high exercise change compared with patients with high psychosocial stress with low exercise change (0% vs 19%; P = .009). In contrast, there was no significant improvement in mortality in patients with high versus low exercise change with low psychosocial stress (4% vs 8%; P = .14).

Conclusion

Psychosocial stress is an independent risk factor for mortality in patients with coronary artery disease, and exercise training can effectively reduce its prevalence. Exercise training reduces mortality in patients with coronary artery disease, and this effect seems to be mediated in part because of the salutary effects of exercise on psychosocial stress.     

Randomized Trial of Nordic Walking in Patients With Moderate to Severe Heart Failure

Background

Patients with heart failure are a growing population within cardiac rehabilitation. The purpose of this study was to compare, through a single-centre, parallel-group, randomized controlled trial, the effects of Nordic walking and standard cardiac rehabilitation care on functional capacity and other outcomes in patients with moderate to severe heart failure.

Methods

Between 2008 and 2009, 54 patients (aged 62.4 ± 11.4 years) with heart failure (mean ejection fraction = 26.9% ± 5.0%) were randomly assigned to standard cardiac rehabilitation care (n = 27) or Nordic walking (n = 27); both groups performed 200 to 400 minutes of exercise per week for 12 weeks. The primary outcome, measured after 12 weeks, was functional capacity assessed by a 6-minute walk test (6MWT).

Results

Compared with standard care, Nordic walking led to higher functional capacity (Δ 125.6 ± 59.4 m vs Δ 57.0 ± 71.3 m travelled during 6MWT; P = 0.001), greater self-reported physical activity (Δ 158.5 ± 118.5 minutes vs Δ 155.5 ± 125.6 minutes; P = 0.049), increased right grip strength (Δ 2.3 ± 3.5 kg vs Δ 0.3 ± 3.1 kg; P = 0.026), and fewer depressive symptoms (Hospital Anxiety and Depression Scale score = Δ −1.7 ± 2.4 vs Δ −0.8 ± 3.1; P = 0.014). No significant differences were found for peak aerobic capacity, left-hand grip strength, body weight, waist circumference, or symptoms of anxiety.

Conclusions

Nordic walking was superior to standard cardiac rehabilitation care in improving functional capacity and other important outcomes in patients with heart failure. This exercise modality is a promising alternative for this population.     

Psychological wellbeing and posttraumatic stress associated with implantable cardioverter defibrillator therapy in young adults with genetic heart disease

Background

Sudden cardiac death is a tragic complication of a number of genetic heart diseases. Implantable cardioverter defibrillator (ICD) therapy plays an important role in prevention of sudden death. The psychological consequences of ICD therapy in young people with genetic heart disease are poorly understood. This study sought to better understand psychological wellbeing and identify symptoms of posttraumatic stress in young people who had experienced an ICD shock.

Methods

Eligible patients (ICD implanted over 12 months prior) with an inherited cardiomyopathy or primary arrhythmogenic disorder, enrolled in the Australian Genetic Heart Disease Registry were included. Ninety patients completed the Hospital Anxiety and Depression Scale (HADS). Those patients who had an ICD shock (n = 31) also completed the Impact of Events Scale-Revised (IES-R).

Results

While the mean HADS-Anxiety and IES-R scores were within the normal range in the total group (n = 90), a significant subgroup reported symptoms of anxiety (38%), depression (17%) and posttraumatic stress (31%) indicative of the potential need for referral to clinical care. Overall, greater psychological distress in ICD patients was associated with female gender, a history of syncope, other comorbid medical conditions, and reporting of other distressing events (i.e., ICD complications). In those with an ICD shock, higher posttraumatic stress scores were associated with female gender and longer time to first shock.

Conclusions

Patients with genetic heart diseases can experience psychological difficulties, including anxiety, depression and posttraumatic stress, related to ICD implantation and subsequent shocks. This signals the importance of offering patients access to targeted interventions, including psychological care and support.     

Impact of exercise training on psychological risk factors

Although the role of psychological risk factors has been underemphasized, considerable evidence indicates the adverse effects of various psychosocial stressors in the pathogenesis and recovery from cardiovascular diseases. Substantial data, especially from cardiac rehabilitation and exercise training programs, have demonstrated the role of physical activity, exercise training, and cardiorespiratory fitness, to improve psychological risk factors, including depression, anxiety, hostility, and total psychological stress, as well as stress-related mortality.     

Impact of cardiac rehabilitation on depression and its associated mortality

Purpose

Depression following major cardiac events is associated with higher mortality, but little is known about whether this can be reduced through treatment including cardiac rehabilitation and exercise training. We evaluated the impact of cardiac rehabilitation on depression and its associated mortality in coronary patients.

Patients and Methods

We evaluated 522 consecutive coronary patients (381 men, 141 women; aged 64 ± 10 years) enrolled in cardiac rehabilitation from January 2000 to July 2005 and a control group of 179 patients not completing rehabilitation. Depressive symptoms were assessed by questionnaire at baseline and following rehabilitation, and mortality was evaluated after a mean follow-up of 1296 ± 551 days.

Results

Prevalence of depressive symptoms decreased 63% following rehabilitation, from 17% to 6% (P <.0001). Depressed patients following rehabilitation had an over 4-fold higher mortality than nondepressed patients (22% vs 5%, P = .0004). Depressed patients who completed rehabilitation had a 73% lower mortality (8% vs 30%; P = .0005) compared with control depressed subjects who did not complete rehabilitation. Reductions in depressive symptoms and its associated mortality were related to improvements in fitness; however, similar reductions were noted in those with either modest or marked increases in exercise capacity.

Conclusion

In patients following major coronary events, cardiac rehabilitation is associated with both reductions in depressive symptoms and the excess mortality associated with it. Moreover, only mild improvements in levels of fitness appear to be needed to produce these benefits on depressive symptoms and its associated mortality.     

Impact of Physical Activity on Depression After Cardiac Surgery

Background

Physical activity is associated with a lower prevalence of depressive symptoms in cardiac patients. However, the benefits of physical activity on depression perioperatively are unknown. We sought to identify independent parameters associated with depression in patients undergoing cardiac surgery.

Methods

Patients awaiting nonemergent cardiac surgery (n = 436) completed the Patient Health Questionnaire-9 (PHQ-9) to quantify depression (PHQ-9 score > 9). Physical activity was assessed with the International Physical Activity Questionnaire (IPAQ-short) and accelerometry. Data collection occurred preoperatively (Q1, n = 436), at hospital discharge (Q2, n = 374), at 3 months (Q3, n = 318), and at 6 months (Q4, n = 342) postoperatively. Patients were categorized as “depression naive”, “at risk” or “depressed” preoperatively. Physical inactivity was defined as < 600 metabolic equivalent min/wk. Independent perioperative variables associated with depression were identified with univariate and multivariate logistic regression.

Results

Depression prevalence from Q1-Q4 was 23%, 37%, 21%, and 23%, respectively. Independent associations with depression were preoperative left ventricular ejection fraction < 50% (Q1, P < 0.05), physical inactivity (Q1, P < 0.05), baseline “at-risk” (Q2, P < 0.05), and baseline “depressed” groups (Q2-Q4, P < 0.05), hospital stay > 7 days (Q2, P < 0.05), postoperative stressful event (Q3 and Q4, P < 0.05), and cardiopulmonary bypass time > 120 minutes (Q4, P = 0.05). Newly depressed patients 6 months postoperatively reported lower IPAQ-short physical activity than depression-free patients (median change, −40 min/wk (interquartile range [IQR], −495 to +255) vs +213 min/wk (IQR, +150 to +830; P < 0.05).

Conclusions

Up to 40% of patients are depressed after cardiac surgery. Preoperative depression and postoperative stressful events were the strongest independent associations postoperatively. Physical inactivity was associated with preoperative depression and new depression 6 months postoperatively.     

Increased Prevalence of Coronary Artery Disease in Severe Psoriasis and Severe Atopic Dermatitis

Background

Psoriasis and atopic dermatitis (AD) are immuno-inflammatory diseases that can result in lifelong systemic inflammation. Unlike AD, psoriasis has been associated with cardiovascular disease. The aim of this study was to examine the prevalence, severity, and subtype of coronary artery disease (CAD) in psoriasis and AD patients without known cardiovascular disease.

Methods

Consecutively enrolled patients (psoriasis n = 58, AD n = 31) and retrospectively matched controls (n = 33) were examined using cardiac computed tomography angiography (CCTA) and assessed using an 18-segment model of the coronary tree.

Results

The prevalence of a coronary artery calcium score >0 was 29.8% in psoriasis and 45.2% in AD, vs 15.2% in controls (P = .09 and P = .01, respectively). More patients with psoriasis had a coronary artery calcium score ≥100 (psoriasis 19.3%, controls 2.9%; P = .02). CCTA showed the presence of plaques in 38.2% of psoriasis patients and 48.1% of AD patients, vs 21.2% of controls (P = .08 and P = .03, respectively). Psoriasis was associated with an increased prevalence of significant coronary stenosis (stenosis >70%) (psoriasis 14.6%, controls 0%; P = .02) and 3-vessel coronary affection or left main artery disease (psoriasis 20%, controls 3%; P = .02), whereas AD was associated with mild (AD 40.7%, controls 9.1%; P = .005) single-vessel affection.

Conclusions

These findings suggest that psoriasis and AD are associated with an increased prevalence of CAD. Patients with psoriasis have an increased prevalence of severe CAD.     

Low exercise blood pressure and risk of cardiovascular events and all-cause mortality: Systematic review and meta-analysis

Objective

The independent prognostic significance of abnormally low systolic blood pressure (SBP) during exercise stress testing (LowExBP) across different clinical and exercise conditions is unknown. We sought by systematic review and meta-analysis to determine the association between cardiovascular/all-cause outcomes and LowExBP across different patient clinical presentations, exercise modes, exercise intensities and categories of LowExBP.

Methods

Seven online databases were searched for longitudinal studies reporting the association of LowExBP with risk of fatal and non-fatal cardiovascular events and/or all-cause mortality. LowExBP was defined as either: SBP drop below baseline; failure to increase >10 mmHg from baseline or; lowest SBP quantile among reporting studies.

Results

After review of 13,257 studies, 19 that adjusted for resting SBP were included in the meta-analysis, with a total of 45,895 participants (average follow-up, 4.4 ± 3.0 years). For the whole population, LowExBP was associated with increased risk for fatal and non-fatal cardiovascular events and all-cause mortality (hazard ratio [HR]: 2.01, 95% confidence interval [CI]: 1.59–2.53, p < 0.001). In continuous analyses, a 10 mmHg decrease in exercise SBP was associated with higher risk (n = 9 HR: 1.13, 95% CI: 1.06–1.20, p < 0.001). LowExBP was associated with increased risk regardless of clinical presentation (coronary artery disease, heart failure, hypertrophic cardiomyopathy or peripheral artery disease), exercise mode (treadmill or bike), exercise intensity (moderate or maximal), or LowExBP category (all p < 0.05). However, bias toward positive results was apparent (Eggers test p < 0.001 and p = 0.009).

Conclusion

Our data show that irrespective of clinical or exercise conditions, LowExBP independently predicts fatal and non-fatal cardiovascular events and all-cause mortality.     

Hiking in Suicidal Patients: Neutral Effects on Markers of Suicidality

Background

Regular physical activity promotes physical and mental health. Psychiatric patients are prone to a sedentary lifestyle, and accumulating evidence has identified physical activity as a supplemental treatment option.

Methods

This prospective, randomized, crossover study evaluated the effects of hiking in high-risk suicidal patients (n = 20) who performed 9 weeks of hiking (2-3 hikes/week, 2-2.5 hours each) and a 9-week control period.

Results

All patients participated in the required 2 hikes per week and thus showed a compliance of 100%. Regular hiking led to significant improvement in maximal exercise capacity (hiking period Δ: +18.82 ± 0.99 watt, P < .001; control period: P = .134) and in aerobic capability at 70% of the individual heart rate reserve (hiking period Δ: +8.47 ± 2.22 watt; P = .010; control period: P = .183). Cytokines, associated previously with suicidality (tumor necrosis factor-α, interleukin-6, S100), remained essentially unchanged.

Conclusions

Hiking is an effective and safe form of exercise training even in high-risk suicidal patients. It leads to a significant improvement in maximal exercise capacity and aerobic capability without concomitant deterioration of markers of suicidality. Offering this popular mode of exercise to these patients might help them to adopt a physically more active lifestyle.     

Psycho-emotional Manifestations of Valvular Heart Diseases: Prospective Assessment in Mitral Regurgitation

Objective

To define the prevalence and consequences of post-traumatic stress disorder (PTSD) as an emotional response to cardiac diseases in patients with mitral regurgitation.

Methods

We prospectively enrolled 186 patients with moderate or severe organic mitral regurgitation, presenting class I (absent) or II (minimal) dyspnea, who were compared with 80 controls of similar age (38 with completely normal cardiac function; 42 with mild mitral-valve prolapse; all with no, or at most mild, mitral regurgitation). Mitral-regurgitation severity and consequences were comprehensively measured, simultaneously with PTSD, anxiety, and depression.

Results

PTSD prevalence was higher in mitral-regurgitation patients vs controls (23% vs 9%, P <.01). Although mitral-regurgitation objective severity (regurgitant volume 77.8 ± 28.9 vs 79.0 ± 27.5 mL, P = .8) and objective consequences (left-atrial volume 59.1 ± 20.9 vs 54.02 ± 15.6 mL, P = .1; right-ventricular systolic pressure 34.1 ± 11.4 vs 32.9 ± 7.2 mm Hg, P = .6) were similar with and without PTSD (all P ≥.1), patients with PTSD were more symptomatic (class II 74 vs 38%; fatigue 71% vs 38%, both P <.0001) and had higher anxiety and depressions scores (P <.0001).

Conclusions

PTSD is prevalent in organic moderate or severe mitral-regurgitation patients but is not determined by objective mitral-regurgitation severity or consequences. PTSD is linked to anxiety and depression and to symptoms usually considered cardiac, such as dyspnea. Thus, PTSD and psycho-emotional manifestations, linked to symptoms, represent important responses to chronic-valve disease that may affect clinical outcomes.     

The effect of cardiac genetic testing on psychological well-being and illness perceptions

Objective

To assess the effects of positive cardiac genetic diagnoses, ICD discharges, and arrhythmias on measures of psychological well-being.

Methods

Fifty-eight adults with prior cardiac genetic testing were enrolled. Patient well-being was determined using the SF-36 (QoL), HADS-A and HADS-D (anxiety/depression), and IPQ-R (patients' perceptions of illness). Patients with positive and negative cardiac genetic test results were compared using non-parametric statistics.

Results

Genetic testing yielded 76% with a positive diagnosis and 29% reported an ICD shock. QoL assessments (n = 33) were within normal ranges (mean of 50) with the exceptions of general health (44.1 ± 12.2, p < 0.01) and bodily pain (55.1 ± 9.1, p < 0.01) domains, but only the bodily pain domain showed differences between those with positive and negative cardiac genetic test results. Subjects with ICD discharges had higher scores than those without shocks in consequential and emotional IPQR subscales as well as greater perceived risks of experiencing a serious cardiac event, developing additional symptoms, or limitations in daily activities.

Conclusion

Positive genetic results did not negatively impact patient well-being with the exception of the bodily pain domain of the SF-36.     

Adverse psychological and coronary risk profiles in young patients with coronary artery disease and benefits of formal cardiac rehabilitation

BACKGROUND: Recent data indicate that young patients with coronary artery disease (CAD) have a poor long-term prognosis. Although the benefits of formal cardiac rehabilitation and exercise training programs are well established, most of these data come from middle-aged and older patients. METHODS: We assessed baseline behavioral data, quality of life, and risk profiles in 635 consecutive patients with CAD before and after cardiac rehabilitation and exercise training, and specifically assessed data in 104 young patients (mean +/- SD age, 48 +/- 6 years; range, 22-54 years) compared with 260 elderly patients (mean +/- SD age, 75 +/- 3 years; range, 70-85 years). RESULTS: Compared with older patients, young patients had higher body mass indexes (12.2%, P<.001), total cholesterol-high-density lipoprotein ratio (14.6%, P<.01), and triglycerides level (27.2%, P<.01), and a lower high-density lipoprotein cholesterol level (-8.8%, P=.045). Young patients also had higher scores for anxiety and hostility (51.5% and 94.4%, respectively; P<.001 for both), a considerably higher prevalence of anxiety (27.9% vs 13.5%; P<.01) and hostility (12.5% vs 4.6%; P<.01) symptoms, and slightly more depression symptoms (23.1% vs 18.8%) compared with elderly patients. Following cardiac rehabilitation and exercise training, young patients had improvements in body mass index (-1.7%, P<.01), percentage body fat (-4.4%, P<.001), high-density lipoprotein cholesterol level (10.2%, P<.001), high-sensitivity C-reactive protein level (-33.3%, P<.01), peak oxygen consumption (11.3%, P<.001), resting heart rate (-4.5%, P=.01), and resting systolic pressure (-2.3%, P=.049), and marked improvements in scores for depression (-58.5%), anxiety (-46.0%), hostility (-45.7%), somatization (-33.8%), and quality of life (15.8%) (P<.001 for all). Young patients also had greater than 50% to greater than 80% reductions in the prevalence of anxiety (P<.001), hostility (P<.01), and depression (P<.001). CONCLUSION: These data demonstrate the adverse psychological and CAD risk profiles that are present in young patients with CAD following major CAD events, and are consistent with substantial benefit of formal cardiac rehabilitation and exercise training programs in younger adults.     

Participation in Cardiac Rehabilitation,Readmissions, and Death After Acute Myocardial Infarction

Background

Participation in cardiac rehabilitation has been shown to decrease mortality after acute myocardial infarction, but its impact on readmissions requires examination.

Methods

We conducted a population-based surveillance study of residents discharged from the hospital after their first-ever myocardial infarction in Olmsted County, Minnesota, from January 1, 1987, to September 30, 2010. Patients were followed up through December 31, 2010. Participation in cardiac rehabilitation after myocardial infarction was determined using billing data. We used a landmark analysis approach (cardiac rehabilitation participant vs not determined by attendance in at least 1 session of cardiac rehabilitation at 90 days post-myocardial infarction discharge) to compare readmission and mortality risk between cardiac rehabilitation participants and nonparticipants accounting for propensity to participate using inverse probability treatment weighting.

Results

Of 2991 patients with incident myocardial infarction, 1569 (52.5%) participated in cardiac rehabilitation after hospital discharge. The cardiac rehabilitation participation rate did not change during the study period, but increased in the elderly and decreased in men and younger patients. After adjustment, cardiac rehabilitation participants had lower all-cause readmission (hazard ratio [HR], 0.75; 95% confidence interval [CI], 0.65-0.87; P < .001), cardiovascular readmission (HR, 0.80; 95% CI, 0.65-0.99; P = .037), noncardiovascular readmission (HR, 0.72; 95% CI, 0.61-0.85; P < .001), and mortality (HR, 0.58; 95% CI, 0.49-0.68; P < .001) risk.

Conclusions

Cardiac rehabilitation participation is associated with a markedly reduced risk of readmission and death after incident myocardial infarction. Improving cardiac rehabilitation participation rates may have a large impact on post-myocardial infarction healthcare resource use and outcomes.     

Cardiac,Obstetric, and Fetal Outcomes During Pregnancy After Biological or Mechanical Aortic Valve Replacement

Background

The aim of this study was to assess pregnancy-related cardiac, maternal, and fetal outcomes in women who underwent aortic valve replacement (AVR).

Methods

From 1978-2011, 67 women < 40 years of age underwent 74 isolated AVRs (52 mechanical prostheses and 22 bioprostheses). All patients were prospectively followed at our dedicated valve clinic. Patients with Turner syndrome, previous hysterectomy, or tubal ligation were excluded. Cardiovascular, obstetric, and fetal outcomes were gathered from medical records and telephone interviews.

Results

A total of 27 pregnancies were reported in 14 patients (bioprosthetic AVR, n = 20; mechanical AVR, n = 7). In the bioprosthetic AVR group, the following adverse events occurred: hospitalizations for syncope (n = 2), prosthetic valve deterioration after pregnancy necessitating reintervention 6 months postpartum (n = 1), miscarriages (n = 9), and preterm birth (n = 1). In the mechanical AVR group, the following adverse events occurred: embolic myocardial infarctions with a decrease in systolic function (n = 2; 1 pregnancy was terminated and 1 was completed), miscarriage (n = 1), postpartum bleeding (n = 1), urgent cesarean section for placental abruption (n = 1), and preterm birth (n = 1).

Conclusions

Findings from this study suggest that pregnancies in women with mechanical AVRs are associated with a higher risk of cardiac and obstetric adverse events. Thus, from this limited cohort, it appears that pregnancies in women with bioprostheses are safer than those in patients with mechanical AVRs.     

A Single Bout of High-Intensity Interval Exercise Does Not Increase Endothelial or Platelet Microparticles in Stable,Physically Fit Men With Coronary Heart Disease

Background

High-intensity interval exercise (HIIE) is gaining in popularity in fitness centres, even among coronary heart disease (CHD) patients. However, whether HIIE can have deleterious acute effects on the vasculature in CHD has not been studied. We hypothesized that when compared with moderate-intensity continuous exercise (MICE), a single bout of HIIE could lead to vascular damage and increasing numbers of circulating endothelial and platelet microparticles (EMPs, PMPs) in stable, physically fit CHD patients.

Methods

Nineteen male CHD patients (aged 62 ± 11 years) underwent, in random order, a single session of HIIE corresponding to 15-second intervals at 100% of peak power output and 15-second passive recovery intervals, and an isocaloric MICE session. EMPs (CD31⁺ and/or CD62E⁺ and CD42b⁻); PMPs (CD42b⁺); nitrates and nitrites; prostacycline; and troponin T, cardiac form (cTnT), were measured 10 minutes before exercise and 20 minutes, 24 hours, and 72 hours after both exercise sessions.

Results

EMPs, PMPs, nitrates and nitrites, prostacycline, and cTnT remained unchanged after both HIIE and MICE exercise sessions. Initial EMP concentration correlated inversely with EMP concentration 20 minutes post exercise, irrespective of exercise modality (r = 0.78, P < 0.0001).

Conclusions

A single HIIE session with very short exercise and passive recovery periods appears safe and does not induce changes to markers of endothelial function. Future studies are required to determine the safety of a long-term HIIE training program.     

Depression and Disease Severity in Patients with Premature Acute Coronary Syndrome

Objectives

The association between depression and cardiovascular disease severity in younger patients has not been assessed, and sex differences are unknown. We assessed whether major depression and depressive symptoms were associated with worse cardiovascular disease severity in patients with premature acute coronary syndrome, and we assessed sex differences in these relationships.

Methods

We enrolled 1023 patients (aged ≤55 years) hospitalized with acute coronary syndrome from 26 centers in Canada, the United States, and Switzerland, through the GENdEr and Sex determInantS of cardiovascular disease: From bench to beyond-Premature Acute Coronary Syndrome study. Left ventricular ejection fraction, Killip class, cardiac troponin I, and Global Registry of Acute Coronary Events score data were collected through chart review.

Results

The sample comprised 248 patients with major depression and 302 women. In univariate analyses, major depression was associated with a lower likelihood of having an abnormal left ventricular ejection fraction (odds ratio, 0.70; 95% confidence interval, 0.51-0.97; P = .03) and lower troponin I levels (estimate, −4.04; 95% confidence interval, −8.01 to −0.06; P = .05). After adjustment for sociodemographic and clinical characteristics, neither major depression nor depressive symptoms were associated with disease severity indices, and there were no sex differences.

Conclusion

The increased risk of adverse events in depressed patients with premature acute coronary syndrome is not explained by disease severity.     

Remote Ischemic Preconditioning Reduces Myocardial Injury in Patients Undergoing Coronary Stent Implantation

Background

Myocardial necrosis occurs frequently in elective percutaneous coronary intervention (PCI) and is associated with subsequent major adverse cardiovascular events (MACEs). This study assessed the protective effect of remote ischemic preconditioning (RIPC) in patients undergoing successful drug-eluting stent implantation with normal baseline troponin values.

Methods

We analyzed 205 participants with normal baseline troponin values undergoing successful coronary stent implantation. Subjects were randomized to 2 groups: The RIPC group (n = 101), whose members received RIPC (created by three 5-minute inflations of a pneumatic medical tourniquet cuff to 200 mm Hg around the upper arm, interspersed with 5-minute intervals of reperfusion) < 2 hours before the PCI procedure, and the control group (n = 104).

Results

The primary outcomes were high sensitive cardiac troponin I (hscTnI) levels and incidence of myocardial infarction (MI 4a, defined as hscTnI > 0.20 ng/mL) at 16 hours after the PCI procedure. The median hscTnI at 16 hours after PCI was lower in the RIPC group compared with the unpreconditioned, control group (0.11 vs 0.21 ng/mL; P < 0.01). The incidence of MI 4a was lower in the RIPC group compared with the control group (39% vs 54%, P < 0.05). Index of renal function showed no difference between the 2 groups at 16 hours after PCI (P > 0.05).

Conclusion

RIPC reduced post-PCI TnI release and incidence of MI 4a in patients undergoing elective coronary stent implantation.     

High-sensitivity cardiac troponin for risk prediction in patients with and without coronary heart disease

Background

In stable patients with unknown coronary anatomy, higher levels of cardiac troponin are associated with an increased risk of cardiovascular events. It was supposed that this association might be explained by the ability of cardiac troponin to detect minor myocardial necrosis which might be caused by subclinical coronary atherosclerosis. Thus, this analysis tested if the predictive value of high-sensitivity troponin T (hsTnT) in stable patients is dependent of the presence or absence of angiographically documented coronary heart disease.

Methods

Stable patients undergoing elective coronary angiography were enrolled (n = 2046). HsTnT was determined before diagnostic procedures. The patients were followed for up to seven years. Primary endpoint was all-cause mortality or non-fatal myocardial infarction. All endpoints were adjudicated by independent physicians. Results were adjusted to a clinical model including independent clinical predictors of the primary endpoint.

Results

Out of the 2046 patients enrolled, 1236 (60%) had a diagnosis of obstructive coronary heart disease. HsTnT predicted independently the primary endpoint (adjusted HR 1.33, 95%-CI 1.21–1.46, P < 0.001). The use of hsTnT in addition to the clinical model significantly improved discrimination (c-statistic: 0.751 to 0.773, P < 0.001) as well as reclassification of the primary endpoint (NRI = 0.362, P < 0.001). This significant improvement persisted across various subsets and was independent of the presence of clinically detectable coronary heart disease and other variables.

Conclusion

The use of hsTnT in addition to clinical variables significantly improves discrimination and reclassification of patients with respect to all-cause mortality or non-fatal myocardial infarction irrespective of the presence of clinically detectable coronary heart disease.

Clinical Trial Registration

ClinicalTrials.gov (Identifier: NCT00457236).     

Myocardium at Risk Is Associated With Adverse Clinical Events in Women but Not in Men,After Coronary Artery Bypass Grafting

Background

Women undergoing coronary artery bypass grafting (CABG) are at increased risk for morbidity and mortality. Factors responsible for this observation include smaller coronary size and delayed presentation. To date, no studies have examined the effect of the degree of myocardium at risk (MAR) on the relationship between female sex and adverse postoperative events.

Methods

Consecutive patients undergoing first-time isolated CABG at a single institution from 2002-2007 were identified. MAR was calculated using the weighted Duke Index and was categorized as low, moderate, or high. Multivariable logistic regression models were created to compare the impact of MAR on adverse clinical events.

Results

We identified 3741 patients, 3325 (89%) of whom had complete angiographic data. Women (n = 755) were older (P = 0.0001) and presented more often with hypertension (P = 0.0001), diabetes (P = 0.0001), heart failure (P = 0.0001), and an urgent/emergent situation (P = 0.002). After surgery, women experienced greater rates of adverse events (15.2% vs 9.3%; P = 0.0001). In a fully adjusted logistic regression model, the nested interaction of sex in MAR showed that women had a significantly greater risk of major adverse cardiovascular events (MACE) when MAR was high (odds ratio [OR], 1.9; 95% confidence interval [CI], 1.3-2.6; P = 0.0004). Greater severity of MAR emerged as an independent predictor of adverse events among women (high: OR, 2.9; 95% CI, 1.2-7.3; moderate: OR, 2.2; 95% CI, 0.8-5.7; low: OR, 1.0), but not among men.

Conclusions

MAR was independently associated with higher rates of adverse events among women but not in men undergoing CABG. This finding may help explain differences in outcomes seen between women and men after revascularization.     

Remote Ischemic Preconditioning and Endothelial Function in Patients with Acute Myocardial Infarction and Primary PCI

Background

Remote ischemic preconditioning by transient limb ischemia reduces myocardial ischemia-reperfusion injury in patients undergoing percutaneous coronary intervention. The aim of the study we report here was to assess the effect of remote ischemic preconditioning on endothelial function in patients with acute myocardial infarction who underwent primary percutaneous coronary intervention.

Methods

Forty-eight patients with acute myocardial infarction were enrolled. All participants were randomly divided into 2 groups. In Group I (n = 23), remote ischemic preconditioning was performed before primary percutaneous coronary intervention (intermittent arm ischemia-reperfusion through 4 cycles of 5-minute inflation and 5-minute deflation of a blood-pressure cuff to 200 mm Hg). In Group II (n = 25), standard percutaneous coronary intervention without preconditioning was performed. We assessed endothelial function using the flow-mediated dilation test on baseline, then within 1-3 hours after percutaneous coronary intervention, and again on days 2 and 7 after percutaneous coronary intervention.

Results

The brachial artery flow-mediated dilation results were significantly higher on the first day after primary percutaneous coronary intervention in the preconditioning group (Group I) than in the control group (Group II) (12.1% vs 0.0%, P = .03, and 11.1% vs 6.3%, P = .016, respectively), and this difference remained on the seventh day (12.3% vs 7.4%, P = .0005, respectively).

Conclusion

We demonstrated for the first time that remote ischemic preconditioning before primary percutaneous coronary intervention significantly improves endothelial function in patients with acute myocardial infarction, and this effect remains constant for at least a week. We suppose that the improvement of endothelial function may be one of the possible explanations of the effect of remote ischemic preconditioning.