Predictors of short- and long-term outcomes of Takotsubo cardiomyopathy

Takotsubo cardiomyopathy (TC) is a reversible cardiomyopathy with a benign short-term prognosis but is associated with recurrence rate of 10%. Clinical variables that predict long-term mortality and recurrence are unknown; 56 consecutive patients presenting to a single urban medical center who fulfilled the Mayo Clinic criteria for the diagnosis of TC were included. Patients were followed with 100% completeness; >60 clinical factors were analyzed, including presentation, treatment, electrocardiogram, and echocardiographic, angiographic, and demographic variables. Survival analysis was performed using the Kaplan-Meier function and Cox proportional hazards regression models. There were 15 deaths during follow-up: 5 in-hospital, 4 before 90 days, and 6 after 90 days. Mean survival was 4.47 years (95% confidence interval 3.81 to 5.13). All short-term survivors had repeat ejection fraction evaluation demonstrating improvement; 45 of 56 patients were women and 96% were postmenopausal. The nonfatal recurrence rate was 1.8%. QTc interval at presentation was the factor most strongly predictive of overall outcome, after intubation. All patients with mortality had QTc intervals between 400 and 550 ms. In conclusion, this study demonstrates the prognostic significance of QTc prolongation at presentation in TC. Because the cause of TC involves intense catecholamine release and hyperadrenergic tone, the QTc may reflect the individual impact on myocardial repolarization and the balance between sympathetic innervation and parasympathetic compensation. In conclusion, in this series, TC was associated with an 8.9% in-hospital mortality, an additional 17.9% mortality after discharge, and a nonfatal recurrence rate of 1.8%. Moreover, the QTc on presentation with TC was predictive of outcome.

Fractional flow reserve: physiological basis, advantages and limitations, and potential gender differences

Fractional flow reserve (FFR) is a physiological index of the severity of a stenosis in an epicardial coronary artery, based on the pressure differential across the stenosis. Clinicians are increasingly relying on this method because it is independent of baseline flow, relatively simple, and cost effective. The accurate measurement of FFR is predicated on maximal hyperemia being achieved by pharmacological dilation of the downstream resistance vessels (arterioles). When the stenosis causes FFR to be impaired by > 20%, it is considered to be significant and to justify revascularization. A diminished hyperemic response due to microvascular dysfunction can lead to a false normal FFR value, and a misguided clinical decision. The blunted vasodilation could be the result of defects in the signaling pathways modulated (activated or inhibited) by the drug. This might involve a downregulation or reduced number of vascular receptors, endothelial impairment, or an increased activity of an opposing vasoconstricting mechanism, such as the coronary sympathetic nerves or endothelin. There are data to suggest that microvascular dysfunction is more prevalent in post-menopausal women, perhaps due to reduced estrogen levels. The current review discusses the historical background and physiological basis for FFR, its advantages and limitations, and the phenomenon of microvascular dysfunction and its impact on FFR measurements. The question of whether it is warranted to apply gender-specific guidelines in interpreting FFR measurements is addressed.

Occupational health hazards of interventional cardiologists in the current decade: Results of the 2014 SCAI membership survey

BACKGROUND

Interventional cardiologists and staff are subject to unique physical demands that predispose them to distinct occupational health hazards not seen in other medical disciplines.

METHODS

To characterize the prevalence of these occupational health problems, The Society for Cardiovascular Angiography and Interventions (SCAI) surveyed its members by email. Inquiries included age, years of invasive practice, and diagnostic and interventional cases per year. Questions focused on orthopedic (spine, hips, knees, and ankles) and radiation-associated problems (cataracts and cancers).

RESULTS

There were 314 responses. Responders were on average busy and experienced, performing a mean of 380±249 diagnostic and 200±129 interventional cases annually. Of the responders, 6.9% of operators have had to limit their caseload because of radiation exposure and 9.3% have had a health-related period of absence. Furthermore, 153 (49.4%) operators reported at least one orthopedic injury: 24.7% cervical spine disease, 34.4% lumbar spine problems, and 19.6% hip, knee or ankle joint problems. Age was most significantly correlated with orthopedic illnesses: cervical injuries (χ2=150.7, P<0.0001); hip/knee or ankle injuries (χ2=80.9, P<0.0001); lumbar injuries (χ2=147.0, P<0.0001); and any orthopedic illness (χ2= 241.2, P<0.0001). Annual total caseload was also associated: the estimated change in the odds of orthopedic illness for each additional total caseload quintile is 1.0013 (1.0001, 1.0026). There is a small but substantial incidence of cancer.

CONCLUSIONS

These findings are consistent with, and extend the findings, of a prior 2004 SCAI survey, in documenting a substantial prevalence of orthopedic complications among active interventional cardiologists, which persists despite increased awareness.

Cost-effectiveness of revascularization strategies: the ASCERT study

BACKGROUND

ASCERT (American College of Cardiology Foundation and the Society of Thoracic Surgeons Collaboration on the Comparative Effectiveness of Revascularization Strategies) was a large observational study designed to compare the long-term effectiveness of coronary artery bypass graft (CABG) and percutaneous coronary intervention (PCI) to treat coronary artery disease (CAD) over 4 to 5 years.

OBJECTIVES

This study examined the cost-effectiveness of CABG versus PCI for stable ischemic heart disease.

METHODS

The Society of Thoracic Surgeons and American College of Cardiology Foundation databases were linked to the Centers for Medicare and Medicaid Services claims data. Costs for the index and observation period (2004 to 2008) hospitalizations were assessed by diagnosis-related group Medicare reimbursement rates; costs beyond the observation period were estimated from average Medicare participant per capita expenditure. Effectiveness was measured via mortality and life-expectancy data. Cost and effectiveness comparisons were adjusted using propensity score matching with the incremental cost-effectiveness ratio expressed as cost per quality-adjusted life-year gained.

RESULTS

CABG patients (n = 86,244) and PCI patients (n = 103,549) were at least 65 years old with 2- or 3-vessel coronary artery disease. Adjusted costs were higher for CABG for the index hospitalization, study period, and lifetime by $10,670, $8,145, and $11,575, respectively. Patients undergoing CABG gained an adjusted average of 0.2525 and 0.3801 life-years relative to PCI over the observation period and lifetime, respectively. The life-time incremental cost-effectiveness ratio of CABG compared to PCI was $30,454/QALY gained.

CONCLUSIONS

Over a period of 4 years or longer, patients undergoing CABG had better outcomes but at higher costs than those undergoing PCI.

Composite outcomes in coronary bypass surgery versus percutaneous intervention

BACKGROUND

Recent observational studies show that patients with multivessel coronary disease have a long-term survival advantage with coronary artery bypass grafting (CABG) compared with percutaneous coronary intervention (PCI). Important nonfatal outcomes may also affect optimal treatment recommendation.

METHODS

CABG was compared with percutaneous catheter intervention by using a composite of death, myocardial infarction (MI), or stroke. Medicare patients undergoing revascularization for stable multivessel coronary disease from 2004 through 2008 were identified in national registries. Short-term clinical information from the registries was linked to Medicare data to obtain long-term follow-up out to 4 years from the time of the procedure. Propensity scoring with inverse probability weighting was used to adjust for baseline risk factors.

RESULTS

There were 86,244 CABG and 103,549 PCI patients. The mean age was 74 years, with a median 2.67 years of follow-up. At 4 years, the propensity-adjusted adjusted cumulative incidence of MI was 3.2% in CABG compared with 6.6% in PCI (risk ratio, 0.49; 95% confidence interval, 0.45 to 0.53). At 4 years, the cumulative incidence of stroke was 4.5% in CABG compared with 3.1% in PCI patients (risk ratio, 1.43; 95% confidence interval, 1.31 to 1.54). This difference was primarily due to the higher 30-day stroke rate for CABG (1.55% vs 0.37%). For the composite of death, MI, or stroke, the 4-year adjusted cumulative incidence was 21.6% for CABG and 26.7% for PCI (risk ratio, 0.81; 95% confidence interval, 0.78 to 0.83).

CONCLUSIONS

The 4-year composite event rate of death, MI, and stroke favored CABG, whereas the risk of stroke alone favored PCI.

Conversations in cardiology: bridging antiplatelet therapy before surgery

Bridging for antiplatelet therapy remains a subject of debate with data favoring GP blockers but at a risk of bleeding. This Conversation in Cardiology addresses a key and often asked question about use of alternatives to P2Y12 agents in patients requiring surgery within 6 months after drug eluting stent implantation.

Angiographic validation of the American College of Cardiology Foundation-the Society of Thoracic Surgeons Collaboration on the Comparative Effectiveness of Revascularization Strategies study

BACKGROUND

The goal of this study was to compare angiographic interpretation of coronary arteriograms by sites in community practice versus those made by a centralized angiographic core laboratory.

METHODS AND RESULTS

The study population consisted of 2013 American College of Cardiology-National Cardiovascular Data Registry (ACC-NCDR) records with 2- and 3- vessel coronary disease from 54 sites in 2004 to 2007. The primary analysis compared Registry (NCDR)-defined 2- and 3-vessel disease versus those from an angiographic core laboratory analysis. Vessel-level kappa coefficients suggested moderate agreement between NCDR and core laboratory analysis, ranging from kappa=0.39 (95% confidence intervals, 0.32-0.45) for the left anterior descending artery to kappa=0.59 (95% confidence intervals, 0.55-0.64) for the right coronary artery. Overall, 6.3% (n=127 out of 2013) of those patients identified with multivessel disease at NCDR sites had had 0- or 1-vessel disease by core laboratory reading. There was no directional bias with regard to overcall, that is, 12.3% of cases read as 3-vessel disease by the sites were read as <3-vessel disease by the core laboratory, and 13.9% of core laboratory 3-vessel cases were read as <3-vessel by the sites. For a subset of patients with left main coronary disease, registry overcall was not linked to increased rates of mortality or myocardial infarction.

CONCLUSIONS

There was only modest agreement between angiographic readings in clinical practice and those from an independent core laboratory. Further study will be needed because the implications for patient management are uncertain.

Consideration of a new definition of clinically relevant myocardial infarction after coronary revascularization: an expert consensus document from the Society for Cardiovascular Angiography and Interventions (SCAI)

Numerous definitions have been proposed for the diagnosis of myocardial infarction (MI) after coronary revascularization. The universal definition for MI designates post procedural biomarker thresholds for defining percutaneous coronary intervention (PCI)-related MI (type 4a) and coronary artery bypass grafting (CABG)-related MI (type 5), which are of uncertain prognostic importance. In addition, for both the MI types, cTn is recommended as the biomarker of choice, the prognostic significance of which is less well validated than CK-MB. Widespread adoption of a MI definition not clearly linked to subsequent adverse events such as mortality or heart failure may have serious consequences for the appropriate assessment of devices and therapies, may affect clinical care pathways, and may result in misinterpretation of physician competence. Rather than using an MI definition sensitive for small degrees of myonecrosis (the occurrence of which, based on contemporary large-scale studies, are unlikely to have important clinical consequences), it is instead recommended that a threshold level of biomarker elevation which has been strongly linked to subsequent adverse events in clinical studies be used to define a "clinically relevant MI." The present document introduces a new definition for "clinically relevant MI" after coronary revascularization (PCI or CABG), which is applicable for use in clinical trials, patient care, and quality outcomes assessment.

Incidence and outcomes of no-reflow phenomenon during percutaneous coronary intervention among patients with acute myocardial infarction

Previous studies describing the no-reflow phenomenon in patients with acute myocardial infarction (AMI) undergoing percutaneous coronary intervention (PCI) were largely confined to single-center studies or small registries. To better characterize the incidence, predictors, and outcomes of the no-reflow phenomenon in a large contemporary population, we analyzed patients with AMI who were undergoing PCI of native coronary artery stenoses in the CathPCI Registry from January 1, 2004 through September 5, 2008 (n = 291,380). The angiographic no-reflow phenomenon was site reported using a standardized definition. No-reflow developed in 2.3% of the patients with AMI (n = 6,553) during PCI. Older age, ST-segment elevation AMI, prolonged interval from symptom onset to admission, and cardiogenic shock were clinical variables independently associated with the development of no-reflow (p <0.001). The angiographic factors independently associated with no-reflow included longer lesion length, higher risk class C lesions, bifurcation lesions, and impaired preprocedure Thrombolysis In Myocardial Infarction flow (p <0.001). No-reflow was associated with greater in-hospital mortality (12.6% vs 3.8%, adjusted odds ratio 2.20, 95% confidence interval 1.97 to 2.47, p <0.001) and unsuccessful lesion outcome (29.7% vs 6.6%, adjusted odds ratio 4.70, 95% confidence interval 4.28 to 5.17, p <0.001) compared to patients without no-reflow. In conclusion, the development of no-reflow, although relatively uncommon during PCI for AMI, is associated with adverse clinical outcomes. Upfront strategies to reduce the incidence of no-reflow could be considered for high-risk patients to improve outcomes.

Temporal trends in and factors associated with bleeding complications among patients undergoing percutaneous coronary intervention: a report from the National Cardiovascular Data CathPCI Registry

OBJECTIVES

The purpose of this study was to examine temporal trends in post-percutaneous coronary intervention (PCI) bleeding among patients with elective PCI, unstable angina (UA)/non-ST-segment elevation myocardial infarction (NSTEMI), and ST-segment elevation myocardial infarction (STEMI).

BACKGROUND

The impact of bleeding avoidance strategies on post-PCI bleeding rates over time is unknown.

METHODS

Using the CathPCI Registry, we examined temporal trends in post-PCI bleeding from 2005 to 2009 among patients with elective PCI (n = 599,524), UA/NSTEMI (n = 836,103), and STEMI (n = 267,632). We quantified the linear time trend in bleeding using 3 sequential logistic regression models: 1) clinical factors; 2) clinical + vascular access strategies (femoral vs. radial, use of closure devices); and 3) clinical, vascular strategies + antithrombotic treatments (anticoagulant ± glycoprotein IIb/IIIa inhibitor [GPI]). Changes in the odds ratio for time trend in bleeding were compared using bootstrapping and converted to risk ratio.

RESULTS

An approximate 20% reduction in post-PCI bleeding was seen (elective PCI: 1.4% to 1.1%; UA/NSTEMI: 2.3% to 1.8; STEMI: 4.9% to 4.5%). Radial approach remained low (<3%), and closure device use increased marginally from 44% to 49%. Bivalirudin use increased (17% to 30%), whereas any heparin + GPI decreased (41% to 28%). There was a significant 6% to 8% per year reduction in annual bleeding risk in UA/NSTEMI and elective PCI, but not in STEMI. Antithrombotic strategies were associated with roughly half of the reduction in annual bleeding risk: change in risk ratio from 7.5% to 4% for elective PCI, and 5.7% to 2.8% for UA/NSTEMI (both p <0.001).

CONCLUSIONS

The nearly 20% reduction in post-PCI bleeding over time was largely due to temporal changes in antithrombotic strategies. Further reductions in bleeding complications may be possible as bleeding avoidance strategies evolve, especially in STEMI.

ACCF/SCAI/STS/AATS/AHA/ASNC/HFSA/SCCT 2012 appropriate use criteria for coronary revascularization focused update: a report of the American College of Cardiology Foundation Appropriate Use Criteria Task Force, Society for Cardiovascular Angiography and Interventions, Society of Thoracic Surgeons, American Association for Thoracic Surgery, American Heart Association, American Society of Nuclear Cardiology, and the Society of Cardiovascular Computed Tomography

The American College of Cardiology Foundation (ACCF), Society for Cardiovascular Angiography and Interventions, Society of Thoracic Surgeons, and the American Association for Thoracic Surgery, along with key specialty and subspecialty societies, conducted an update of the appropriate use criteria (AUC) for coronary revascularization frequently considered. In the initial document, 180 clinical scenarios were developed to mimic patient presentations encountered in everyday practice and included information on symptom status, extent of medical therapy, risk level as assessed by noninvasive testing, and coronary anatomy. This update provides a reassessment of clinical scenarios the writing group felt to be affected by significant changes in the medical literature or gaps from prior criteria. The methodology used in this update is similar to the initial document, and the definition of appropriateness was unchanged. The technical panel scored the clinical scenarios on a scale of 1 to 9. Scores of 7 to 9 indicate that revascularization is considered appropriate and likely to improve patients' health outcomes or survival. Scores of 1 to 3 indicate revascularization is considered inappropriate and unlikely to improve health outcomes or survival. Scores in the mid-range (4 to 6) indicate a clinical scenario for which the likelihood that coronary revascularization will improve health outcomes or survival is uncertain. In general, as seen with the prior AUC, the use of coronary revascularization for patients with acute coronary syndromes and combinations of significant symptoms and/or ischemia is appropriate. In contrast, revascularization of asymptomatic patients or patients with low-risk findings on noninvasive testing and minimal medical therapy are viewed less favorably. The technical panel felt that based on recent studies, coronary artery bypass grafting remains an appropriate method of revascularization for patients with high burden of coronary artery disease (CAD). Additionally, percutaneous coronary intervention may have a role in revascularization of patients with high burden of CAD. The primary objective of the appropriate use criteria is to improve physician decision making and patient education regarding expected benefits from revascularization and to guide future research.

Comparative effectiveness of revascularization strategies

BACKGROUND

Questions persist concerning the comparative effectiveness of percutaneous coronary intervention (PCI) and coronary-artery bypass grafting (CABG). The American College of Cardiology Foundation (ACCF) and the Society of Thoracic Surgeons (STS) collaborated to compare the rates of long-term survival after PCI and CABG.

METHODS

We linked the ACCF National Cardiovascular Data Registry and the STS Adult Cardiac Surgery Database to claims data from the Centers for Medicare and Medicaid Services for the years 2004 through 2008. Outcomes were compared with the use of propensity scores and inverse-probability-weighting adjustment to reduce treatment-selection bias.

RESULTS

Among patients 65 years of age or older who had two-vessel or three-vessel coronary artery disease without acute myocardial infarction, 86,244 underwent CABG and 103,549 underwent PCI. The median follow-up period was 2.67 years. At 1 year, there was no significant difference in adjusted mortality between the groups (6.24% in the CABG group as compared with 6.55% in the PCI group; risk ratio, 0.95; 95% confidence interval [CI], 0.90 to 1.00). At 4 years, there was lower mortality with CABG than with PCI (16.4% vs. 20.8%; risk ratio, 0.79; 95% CI, 0.76 to 0.82). Similar results were noted in multiple subgroups and with the use of several different analytic methods. Residual confounding was assessed by means of a sensitivity analysis.

CONCLUSIONS

In this observational study, we found that, among older patients with multivessel coronary disease that did not require emergency treatment, there was a long-term survival advantage among patients who underwent CABG as compared with patients who underwent PCI. (Funded by the National Heart, Lung, and Blood Institute.).

Prediction of long-term mortality after percutaneous coronary intervention in older adults: results from the National Cardiovascular Data Registry

BACKGROUND

The purpose of this study was to develop a long-term model to predict mortality after percutaneous coronary intervention in both patients with ST-segment elevation myocardial infarction and those with more stable coronary disease.

METHODS AND RESULTS

The American College of Cardiology Foundation CathPCI Registry data were linked to the Centers for Medicare and Medicaid Services 100% denominator file by probabilistic matching. Preprocedure demographic and clinical variables from the CathPCI Registry were used to predict the probability of death over 3 years as recorded in the Centers for Medicare and Medicaid Services database. Between 2004 and 2007, 343 466 patients (66%) of 518 195 patients aged ≥65 years undergoing first percutaneous coronary intervention in the CathPCI Registry were successfully linked to Centers for Medicare and Medicaid Services data. This study population was randomly divided into 60% derivation and 40% validation cohorts. Median follow-up was 15 months, with mortality of 3.0% at 30 days and 8.7%, 13.4%, and 18.7% at 1, 2, and 3 years, respectively. Twenty-four characteristics related to demographics, clinical comorbidity, prior history of disease, and indices of disease severity and acuity were identified as being associated with mortality. The C indices in the validation cohorts for patients with and without ST-segment elevation myocardial infarction were 0.79 and 0.78. The model calibrated well across a wide range of predicted probabilities.

CONCLUSIONS

On the basis of the large and nationally representative CathPCI Registry, we have developed a model that has excellent discrimination, calibration, and validation to predict survival up to 3 years after percutaneous coronary intervention.