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Despite aspirin's and clopidogrel's proven benefit in reducing cardiovascular (CV) events, recurrent CV events still occur in patients receiving antiplatelet therapy. Many of these patients are resistant or only partially responsive to the antiplatelet effects of aspirin and clopidogrel, as determined by standard platelet assays. However, current clinical guidelines do not support routine screening for aspirin or clopidogrel resistance, in part because determination of the most appropriate screening test has not been established. This review attempts to (1) describe the phenomena of clinical aspirin and clopidogrel resistance (ie, treatment failure), (2) discuss the complexity of defining and identifying aspirin and clopidogrel resistance, (3) identify factors that may be responsible for aspirin and clopidogrel resistance, (4) outline several standard platelet function assays and their limitations, and (5) describe potential new antiplatelet therapies that may benefit aspirin- or clopidogrel-resistant patients. [ABSTRACT FROM AUTHOR]

Academic medical centers are rapidly evolving into academic health systems with expanding clinical activity. These changes coupled with financial pressures due to decreased clinical reimbursements and failure of the NHLBI budget to keep pace with inflation are challenging the ability to succeed in all our missions. New governance structures and financial models may be necessary to success in our research and educational missions., (© 2023 The American Clinical and Climatological Association.)

A 79-year-old Caucasian male was referred to cardiology clinic because the electrocardiogram showed premature atrial complexes and pre-excitation (delta waves) thought to be consistent with Wolff-Parkinson-White (WPW) syndrome. He did not report symptoms of palpitations or syncope. Careful analysis of the electrocardiogram revealed a fascicular-ventricular pathway (FVP) responsible for pre-excitation. Differentiating FVP from WPW syndrome is essential as the risk profile is different with each. Electrocardiographic observations that could help identify the presence of an FVP and its diagnostic, prognostic, and therapeutic implications are presented.

Background: Disseminated nontuberculous mycobacterium infections have occurred following surgical procedures involving extracorporeal circulation; contaminated water from heater-cooler devices (HCDs) has been implicated as the source. The purpose of this review was to evaluate the public health concern and to educate physicians who care for this patient population., Methods: The Food and Drug Administration Medical Device Reporting (MDR) database was queried for reports received between January 2010 and August 2016 for patient infections and device contaminations associated with the use of HCDs. Reports were reviewed for type of infection, patient demographics or outcome, reporting country, HCD manufacturer, and the time to event occurrence., Results: A total of 339 MDR reports involving 99 facilities and 5 HCD manufacturers were found. MDR reports originated within (n = 154) and outside the United States (n = 185), and included 107 MDR reports describing patient infections involving at least 86 patients and 232 MDR reports describing HCD contamination without known patient infections. The MDR reports identified the surgical procedure in 94 reports and infection location in 83 reports. The time from surgical procedure using an HCD to infection diagnosis was calculable in 67 reports and was reported up to 60 months following the initial surgery. Nontuberculous mycobacterium was the most frequent organism identified, with M. chimaera being the predominate isolate., Conclusions: Nontuberculous mycobacterium infections associated with HCDs used during cardiothoracic surgery may have a long latency period and may be lethal. Cardiothoracic surgeon awareness or involvement in this issue is critical in helping to mitigate this emerging public health concern., (Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Despite numerous advances in the prevention and treatment of atherosclerosis, cardiovascular disease remains a leading cause of morbidity and mortality. Novel and inexpensive interventions that can contribute to the primary and secondary prevention of cardiovascular disease are of interest. Numerous studies have reported on the benefits of meditation. Meditation instruction and practice is widely accessible and inexpensive and may thus be a potential attractive cost-effective adjunct to more traditional medical therapies. Accordingly, this American Heart Association scientific statement systematically reviewed the data on the potential benefits of meditation on cardiovascular risk. Neurophysiological and neuroanatomical studies demonstrate that meditation can have long-standing effects on the brain, which provide some biological plausibility for beneficial consequences on the physiological basal state and on cardiovascular risk. Studies of the effects of meditation on cardiovascular risk have included those investigating physiological response to stress, smoking cessation, blood pressure reduction, insulin resistance and metabolic syndrome, endothelial function, inducible myocardial ischemia, and primary and secondary prevention of cardiovascular disease. Overall, studies of meditation suggest a possible benefit on cardiovascular risk, although the overall quality and, in some cases, quantity of study data are modest. Given the low costs and low risks of this intervention, meditation may be considered as an adjunct to guideline-directed cardiovascular risk reduction by those interested in this lifestyle modification, with the understanding that the benefits of such intervention remain to be better established. Further research on meditation and cardiovascular risk is warranted. Such studies, to the degree possible, should utilize randomized study design, be adequately powered to meet the primary study outcome, strive to achieve low drop-out rates, include long-term follow-up, and be performed by those without inherent bias in outcome., (© 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.)

Background: Proteolytically released extracellular matrix (ECM) fragments, matricryptins, are biologically active and play important roles in wound healing. Following myocardial infarction (MI), collagen I, a major component of cardiac ECM, is cleaved by matrix metalloproteinases (MMPs)., Objectives: This study identified novel collagen-derived matricryptins generated post-MI that mediate remodeling of the left ventricle (LV)., Methods: Recombinant collagen Ia1 was used in MMPs cleavage assays, the products were analyzed by mass spectrometry for identification of cleavage sites. C57BL6/J mice were given MI and animals were treated either with vehicle control or p1158/59 matricryptin. Seven days post-MI, LV function and parameters of LV remodeling were measured. Levels of p1158/59 were also measured in plasma of MI patients and healthy controls., Results: In situ, MMP-2 and -9 generate a collagen Iα1 C-1158/59 fragment, and MMP-9 can further degrade it. The C-1158/59 fragment was identified post-MI, both in human plasma and mouse LV, at levels that inversely correlated to MMP-9 levels. We synthesized a peptide beginning at the cleavage site (p1158/59, amino acids 1159 to 1173) to investigate its biological functions. In vitro, p1158/59 stimulated fibroblast wound healing and robustly promoted angiogenesis. In vivo, early post-MI treatment with p1158/59 reduced LV dilation at day 7 post-MI by preserving LV structure (p < 0.05 vs. control). The p1158/59 stimulated both in vitro and in vivo wound healing by enhancing basement membrane proteins, granulation tissue components, and angiogenic factors., Conclusions: Collagen Iα1 matricryptin p1158/59 facilitates LV remodeling post-MI by regulating scar formation through targeted ECM generation and stimulation of angiogenesis., (Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

The year 2014 marked the 20th anniversary of the coining of the term proteomics. The purpose of this scientific statement is to summarize advances over this period that have catalyzed our capacity to address the experimental, translational, and clinical implications of proteomics as applied to cardiovascular health and disease and to evaluate the current status of the field. Key successes that have energized the field are delineated; opportunities for proteomics to drive basic science research, facilitate clinical translation, and establish diagnostic and therapeutic healthcare algorithms are discussed; and challenges that remain to be solved before proteomic technologies can be readily translated from scientific discoveries to meaningful advances in cardiovascular care are addressed. Proteomics is the result of disruptive technologies, namely, mass spectrometry and database searching, which drove protein analysis from 1 protein at a time to protein mixture analyses that enable large-scale analysis of proteins and facilitate paradigm shifts in biological concepts that address important clinical questions. Over the past 20 years, the field of proteomics has matured, yet it is still developing rapidly. The scope of this statement will extend beyond the reaches of a typical review article and offer guidance on the use of next-generation proteomics for future scientific discovery in the basic research laboratory and clinical settings., (© 2015 American Heart Association, Inc.)

Since the modern era of cancer chemotherapy that began in the mid-1940s, survival rates for children afflicted with cancer have steadily improved from 10% to current rates that approach 80% (60). Unfortunately, many long-term survivors of pediatric cancer develop chemotherapy-related health effects; 25% are afflicted with a severe or life-threatening medical condition, with cardiovascular disease being a primary risk (96). Childhood cancer survivors have markedly elevated incidences of stroke, congestive heart failure (CHF), coronary artery disease, and valvular disease (96). Their cardiac mortality is 8.2 times higher than expected (93). Anthracyclines are a key component of most curative chemotherapeutic regimens used in pediatric cancer, and approximately half of all childhood cancer patients are exposed to them (78). Numerous epidemiologic and observational studies have linked childhood anthracycline exposure to an increased risk of developing cardiomyopathy and CHF, often decades after treatment. The acute toxic effects of anthracyclines on cardiomyocytes are well described; however, myocardial tissue is comprised of additional resident cell types, and events occurring in the cardiomyocyte do not fully explain the pathological processes leading to late cardiomyopathy and CHF. This review will summarize the current literature regarding the cellular and molecular responses to anthracyclines, with an important emphasis on nonmyocyte cardiac cell types as well as those that mediate the myocardial injury response., (Copyright © 2014 the American Physiological Society.)

Vast research efforts have been devoted to providing clinical diagnostic markers of myocardial infarction (MI), leading to over one million abstracts associated with "MI" and "Cardiovascular Diseases" in PubMed. Accumulation of the research results imposed a challenge to integrate and interpret these results. To address this problem and better understand how the left ventricle (LV) remodels post-MI at both the molecular and cellular levels, we propose here an integrative framework that couples computational methods and experimental data. We selected an initial set of MI-related proteins from published human studies and constructed an MI-specific protein-protein-interaction network (MIPIN). Structural and functional analysis of the MIPIN showed that the post-MI LV exhibited increased representation of proteins involved in transcriptional activity, inflammatory response, and extracellular matrix (ECM) remodeling. Known plasma or serum expression changes of the MIPIN proteins in patients with MI were acquired by data mining of the PubMed and UniProt knowledgebase, and served as a training set to predict unlabeled MIPIN protein changes post-MI. The predictions were validated with published results in PubMed, suggesting prognosticative capability of the MIPIN. Further, we established the first knowledge map related to the post-MI response, providing a major step towards enhancing our understanding of molecular interactions specific to MI and linking the molecular interaction, cellular responses, and biological processes to quantify LV remodeling.

Background: The Fick principle (cardiac output = oxygen uptake ( O2)/systemic arterio-venous oxygen difference) is used to determine cardiac output in numerous clinical situations. However, estimated rather than measured O2 is commonly used because of complexities of the measurement, though the accuracy of estimation remains uncertain in contemporary clinical practice., Methods and Results: From 1996 to 2005, resting O2 was measured via the Douglas bag technique in adult patients undergoing right heart catheterization. Resting O2 was estimated by each of 3 published formulae. Agreement between measured and estimated O2 was assessed overall, and across strata of body mass index, sex, and age. The study included 535 patients, with mean age 55 yrs, mean body mass index 28.4 kg/m2; 53% women; 64% non-white. Mean (±standard deviation) measured O2 was 241 ± 57 ml/min. Measured O2 differed significantly from values derived from all 3 formulae, with median (interquartile range) absolute differences of 28.4 (13.1, 50.2) ml/min, 37.7 (19.4, 63.3) ml/min, and 31.7 (14.4, 54.5) ml/min, for the formulae of Dehmer, LaFarge, and Bergstra, respectively (P<0.0001 for each). The measured and estimated values differed by >25% in 17% to 25% of patients depending on the formula used. Median absolute differences were greater in severely obese patients (body mass index > 40 kg/m2), but were not affected by sex or age., Conclusions: Estimates of resting O2 derived from conventional formulae are inaccurate, especially in severely obese individuals. When accurate hemodynamic assessment is important for clinical decision-making, O2 should be directly measured.

Objective: To evaluate the prognostic significance of baseline electrocardiogram (ECG) abnormalities in a multiethnic cohort of patients with early systemic sclerosis (SSc) and to determine the serological, clinical, and echocardiogram correlates of ECG findings., Methods: SSc patients with disease duration of≤5 years were enrolled in the GENISOS (Genetics versus Environment in Scleroderma Outcome Study) cohort. At the first visit, a standard 12 lead ECG was obtained along with demographic information, clinical data, and autoantibodies. The results of echocardiograms were also recorded. All ECGs were interpreted by a cardiologist unaware of the patients' clinical data., Results: Of 265 SSc patients with average disease duration at enrollment of 2.5 years, 140 (52.8%) had abnormal ECG findings. These findings were not associated with SSc disease type or autoantibody profile but were associated with more severe heart and lung involvement. A total of 75 patients (28.3%) died over a follow up time of 9.9 years. Complete right bundle branch block (± left anterior hemiblock) on ECG, present in 7 (2.6%) patients, predicted a higher risk of mortality (HR: 5.3; 95% CI: 2.1 to 13.4; p<0.001). The predictive significance of right bundle branch block was independent of age at enrollment, gender, ethnicity and risk factors for coronary artery disease., Conclusion: ECG abnormalities are common in patients with early SSc and are associated with the severity of lung and heart involvement. Right bundle branch block is an independent predictor of mortality, and should be considered a marker of disease severity in SSc.

Objectives: The purpose of this study was to assess whether: 1) very small increases in troponin T, measured by a new highly sensitive cardiac troponin T (hs-cTnT), may reflect ischemia without necrosis; and 2) serial changes can discriminate ischemia from other causes of cardiac troponin T (cTnT) release., Background: A new hs-cTnT assay offers greater sensitivity than current assays., Methods: Nineteen patients referred for diagnostic catheterization underwent cannulation of the coronary sinus (CS). Serial CS and peripheral plasma samples were obtained at multiple time points during and after incremental rapid atrial pacing. cTnT was quantified using both a standard and a pre-commercial highly sensitive assay. Ischemia was determined by the presence of significant coronary artery disease (CAD) and myocardial lactate release with pacing., Results: cTnT concentrations in CS blood increased from a median of 6.8 pg/ml prior to pacing to 15.6 pg/ml 60 min after termination of rapid atrial pacing (p < 0.0001), changes that were mirrored at 180 min in peripheral blood (5.1 to 11.8 pg/ml, p < 0.0001). Although peripheral cTnT concentrations tended to be higher at 180 min following pacing for patients with CAD and lactate elution (n = 7) when compared with those without either marker (n = 5) (25.0 pg/ml vs. 10.2 pg/ml, p = 0.10), relative (1.7-fold vs. 5.2-fold) and absolute (6.8 pg/ml vs. 8.8 pg/ml, p = 0.50) changes were not different between groups., Conclusions: Brief periods of ischemia, without frank infarction, cause low-level cTnT release, and small increases are common after periods of increased myocardial work, even among patients without objective evidence of myocardial ischemia or obstructive CAD. Additional research is needed before hs-cTnT assays are widely adopted in the management of subjects with chest pain syndromes., (Copyright © 2011 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

A rigorous analysis of the torsional modes in both a cylindrical wave guide and the associated static viscous fluid field has been conducted from the solid and the fluid wave equations and the coupled boundary conditions. As a result, two acoustic viscometer models, along with four independent equations connecting the density and the viscosity of the fluid with the attenuation and the phase velocity of the torsional wave in the wave guide, have been developed. The analysis shows that the product of the viscosity and the density of the fluid can be measured from the end reflection coefficient of the torsional wave in the wave guide and that both the viscosity and the density can be determined simultaneously from either the phase velocity or the attenuation of the torsional wave in a single cylindrical wave guide. For the simultaneous measurements of the viscosity and the density, the independent equations have to be solved numerically, for example, using Matlab (The MathWorks, Natick, MA), given either the attenuation or the phase velocity in the wave guide that is surrounded by the fluid. To demonstrate the technical feasibility, numerical simulations have been conducted to discern viscosity, phase velocity, and density, all versus attenuation, at different frequencies, and with variable dimension of a molybdenum rod, so that both the advantages and the disadvantages of the simultaneous measurements can be explored. In the end, to test the two models, preliminary experiments on two viscous standards were conducted at 23 degrees C, and good agreements have been achieved between the viscosities measured from both models and for both standards.

Background: After successful percutaneous coronary arterial revascularization, 25% to 60% of subjects have restenosis, a recurrent coronary arterial narrowing at the site of the intervention. At present, restenosis is usually detected invasively with contrast coronary angiography. This study was performed to determine if phase-contrast MRI (PC-MRI) could be used to detect restenosis noninvasively in patients with recurrent chest pain after percutaneous revascularization., Methods and Results: Seventeen patients (15 men, 2 women, age 36 to 77 years) with recurrent chest pain >3 months after successful percutaneous intervention underwent PC-MRI measurements of coronary artery flow reserve followed by assessments of stenosis severity with computer-assisted quantitative coronary angiography. The intervention was performed in the left anterior descending coronary artery in 15 patients, one of its diagonal branches in 2 patients, and the right coronary artery in 1 patient. A PC-MRI coronary flow reserve value /=70% and >/=50%, respectively., Conclusions: Assessments of coronary flow reserve with PC-MRI can be used to identify flow-limiting stenoses (luminal diameter narrowings >70%) in patients with recurrent chest pain in the months after a successful percutaneous intervention.

Almost all mitral stenosis (MS) is rheumatic in etiology. The patient with MS who is symptomatic despite medical therapy should undergo percutaneous mitral balloon valvuloplasty or mitral valvular surgery (commissurotomy or replacement). The choice of procedure is determined by patient preference and the echocardiographic morphologic features of the valvular and subvalvular apparati. With balloon valvuloplasty, the rate of success is > 90%. At institutions where operators are experienced with balloon valvuloplasty and open surgical commissurotomy, their acute and long-term results are comparable. Balloon valvuloplasty occasionally is associated with complications, including death in 0 to 1%, moderate or severe valvular regurgitation in 3 to 5%, and systemic embolization in 1 to 3%.

Background: Coronary artery bypass grafting improves survival in patients with >70% luminal diameter narrowing of the 3 major epicardial coronary arteries, particularly if there is involvement of the proximal portion of the left anterior descending (LAD) coronary artery. Measurement of coronary flow reserve can be used to identify functionally important luminal narrowing of the LAD artery. Although magnetic resonance imaging (MRI) has been used to visualize coronary arteries and to measure flow reserve noninvasively, the utility of MRI for detecting significant LAD stenoses is unknown., Methods and Results: Thirty subjects (23 men, 7 women, age 36 to 77 years) underwent MRI visualization of the left main and LAD coronary arteries as well as measurement of flow in the proximal, middle, or distal LAD both at rest and after intravenous adenosine (140 microgram/kg per minute). Immediately thereafter, contrast coronary angiography and when feasible, intracoronary Doppler assessments of coronary flow reserve, were performed. There was a statistically significant correlation between MRI assessments of coronary flow reserve and (a) assessments of coronary arterial stenosis severity by quantitative coronary angiography and (b) invasive measurements of coronary flow reserve (P<0.0001 for both). In comparison to computer-assisted quantitative coronary angiography, the sensitivity and specificity of MRI for identifying a stenosis >70% in the distal left main or proximal/middle LAD arteries was 100% and 83%, respectively., Conclusions: Noninvasive MRI measures of coronary flow reserve correlated well with similar measures obtained with the use of intracoronary Doppler flow wires and predicted significant coronary stenoses (>70%) with a high degree of sensitivity and specificity. MRI-based measurement of coronary flow reserve may prove useful for identification of patients likely to obtain a survival benefit from coronary artery bypass grafting.

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Background: In dogs, a large amount of intravenous cocaine causes a profound deterioration of left ventricular (LV) systolic function and an increase in LV end-diastolic pressure. This study was done to assess the influence of a high intracoronary cocaine concentration on LV systolic and diastolic function in humans., Methods and Results: In 20 patients (14 men and 6 women aged 39 to 72 years) referred for cardiac catheterization for the evaluation of chest pain, we measured heart rate, systemic arterial pressure, LV pressure and its first derivative (dP/dt), and LV volumes and ejection fraction before and during the final 2 to 3 minutes of a 15-minute intracoronary infusion of saline (n=10, control subjects) or cocaine hydrochloride 1 mg/min (n=10). No variable changed with saline. With cocaine, the drug concentration in blood obtained from the coronary sinus was 3.0+/-0.4 (mean+/-SD) mg/L, similar in magnitude to the blood cocaine concentration reported in abusers dying of cocaine intoxication. Cocaine induced no significant change in heart rate, LV dP/dt (positive or negative), or LV end-diastolic volume, but it caused an increase in systolic and mean arterial pressures, LV end-diastolic pressure, and LV end-systolic volume, as well as a decrease in LV ejection fraction., Conclusions: In humans, the intracoronary infusion of cocaine sufficient in amount to achieve a high drug concentration in coronary sinus blood causes a deterioration of LV systolic and diastolic performance.

In survivors of acute myocardial infarction, the restoration of antegrade flow in the infarct-related coronary artery may improve prognosis by a mechanism independent of its effect on left ventricular function. Survival may be enhanced even when restoration of flow is accomplished days or weeks after the acute event. In a series of retrospective studies of survivors of a first myocardial infarction, it was shown that long-term survival is significantly better in those with than in those without antegrade flow in the infarct-related artery. It is hypothesized that late restoration of antegrade flow in the infarct-related artery renders the border zone of the infarction more electrically stable, thereby diminishing the incidence of ventricular tachyarrhythmias and sudden death.