Effect of continuous and interval exercise training on the PETCO2 response during a graded exercise test in patients with coronary artery disease

OBJECTIVE: The purpose of this study was to evaluate the following: 1) the effects of continuous exercise training and interval exercise training on the end-tidal carbon dioxide pressure (PETCO2) response during a graded exercise test in patients with coronary artery disease; and 2) the effects of exercise training modalities on the association between PETCO2 at the ventilatory anaerobic threshold (VAT) and indicators of ventilatory efficiency and cardiorespiratory fitness in patients with coronary artery disease. METHODS: Thirty-seven patients (59.7 +/- 1.7 years) with coronary artery disease were randomly divided into two groups: continuous exercise training (n = 20) and interval exercise training (n = 17). All patients performed a graded exercise test with respiratory gas analysis before and after three months of the exercise training program to determine the VAT, respiratory compensation point (RCP) and peak oxygen consumption. RESULTS: After the interventions, both groups exhibited increased cardiorespiratory fitness. Indeed, the continuous exercise and interval exercise training groups demonstrated increases in both ventilatory efficiency and PETCO2 values at VAT, RCP, and peak of exercise. Significant associations were observed in both groups: 1) continuous exercise training (PETCO(2)VAT and cardiorespiratory fitness r = 0.49; PETCO(2)VAT and ventilatory efficiency r = -0.80) and 2) interval exercise training (PETCO(2)VAT and cardiorespiratory fitness r = 0.39; PETCO(2)VAT and ventilatory efficiency r = -0.45). CONCLUSIONS: Both exercise training modalities showed similar increases in PETCO2 levels during a graded exercise test in patients with coronary artery disease, which may be associated with an improvement in ventilatory efficiency and cardiorespiratory fitness.

Ticagrelor Versus Clopidogrel in Patients With Acute Coronary Syndromes and a History of Stroke or Transient Ischemic Attack

Background-Patients with acute coronary syndromes and history of stroke or transient ischemic attack (TIA) have an increased rate of recurrent cardiac events and intracranial hemorrhages. Methods and Results-We evaluated treatment effects of ticagrelor versus clopidogrel in patients with acute coronary syndrome with and without a history of prior stroke or TIA in the PLATelet inhibition and patient Outcomes (PLATO) trial. Of the 18 624 randomized patients, 1152 (6.2%) had a history of stroke or TIA. Such patients had higher rates of myocardial infarction (11.5% versus 6.0%), death (10.5% versus 4.9%), stroke (3.4% versus 1.2%), and intracranial bleeding (0.8% versus 0.2%) than patients without prior stroke or TIA. Among patients with a history of stroke or TIA, the reduction of the primary composite outcome and total mortality at 1 year with ticagrelor versus clopidogrel was consistent with the overall trial results: 19.0% versus 20.8% (hazard ratio, 0.87; 95% confidence interval, 0.66-1.13; interaction P=0.84) and 7.9% versus 13.0% (hazard ratio, 0.62; 95% confidence interval, 0.42-0.91). The overall PLATO-defined bleeding rates were similar: 14.6% versus 14.9% (hazard ratio, 0.99; 95% confidence interval, 0.71-1.37), and intracranial bleeding occurred infrequently (4 versus 4 cases, respectively). Conclusions-Patients with acute coronary syndrome with a prior history of ischemic stroke or TIA had higher rates of clinical outcomes than patients without prior stroke or TIA. However, the efficacy and bleeding results of ticagrelor in these high-risk patients were consistent with the overall trial population, with a favorable clinical net benefit and associated impact on mortality.

Interaction between Advanced Glycation End Products Formation and Vascular Responses in Femoral and Coronary Arteries from Exercised Diabetic Rats

Background: The majority of studies have investigated the effect of exercise training (TR) on vascular responses in diabetic animals (DB), but none evaluated nitric oxide (NO) and advanced glycation end products (AGEs) formation associated with oxidant and antioxidant activities in femoral and coronary arteries from trained diabetic rats. Our hypothesis was that 8-week TR would alter AGEs levels in type 1 diabetic rats ameliorating vascular responsiveness. Methodology/Principal Findings: Male Wistar rats were divided into control sedentary (C/SD), sedentary diabetic (SD/DB), and trained diabetic (TR/DB). DB was induced by streptozotocin (i.p.: 60 mg/kg). TR was performed for 60 min per day, 5 days/week, during 8 weeks. Concentration-response curves to acetylcholine (ACh), sodium nitroprusside (SNP), phenylephrine (PHE) and tromboxane analog (U46619) were obtained. The protein expressions of eNOS, receptor for AGEs (RAGE), Cu/Zn-SOD and Mn-SOD were analyzed. Tissues NO production and reactive oxygen species (ROS) generation were evaluated. Plasma nitrate/nitrite (NOx-), superoxide dismutase (SOD), catalase (CAT), thiobarbituric acid reactive substances (TBARS) and N-epsilon-(carboxymethyl) lysine (CML, AGE biomarker). A rightward shift in the concentration-response curves to ACh was observed in femoral and coronary arteries from SD/DB that was accompanied by an increase in TBARS and CML levels. Decreased in the eNOS expression, tissues NO production and NOx- levels were associated with increased ROS generation. A positive interaction between the beneficial effect of TR on the relaxing responses to ACh and the reduction in TBARS and CML levels were observed without changing in antioxidant activities. The eNOS protein expression, tissues NO production and ROS generation were fully re-established in TR/DB, but plasma NOx- levels were partially restored. Conclusion: Shear stress induced by TR fully restores the eNOS/NO pathway in both preparations from non-treated diabetic rats, however, a massive production of AGEs still affecting relaxing responses possibly involving other endothelium-dependent vasodilator agents, mainly in coronary artery.

Late remote ischemic preconditioning in children undergoing cardiopulmonary bypass: A randomized controlled trial

Objective: Cardiopulmonary bypass is associated with ischemia-reperfusion injury to multiple organs. We aimed to evaluate whether remote ischemic preconditioning performed the day before surgery for congenital heart disease with cardiopulmonary bypass attenuates the postoperative inflammatory response and myocardial dysfunction. Methods: This was a prospective, randomized, single-blind, controlled trial. Children allocated to remote ischemic preconditioning underwent 4 periods of 5 minutes of lower limb ischemia by a blood pressure cuff intercalated with 5 minutes of reperfusion. Blood samples were collected 4, 12, 24, and 48 hours after cardiopulmonary bypass to evaluate nuclear factor kappa B activation in leukocytes by quantification of mRNA of I kappa B alpha by real-time quantitative polymerase chain reaction and for interleukin-8 and 10 plasma concentration measurements by enzyme-linked immunosorbent assay. Myocardial dysfunction was assessed by N-terminal pro-B-type natriuretic peptide and cardiac troponin I plasma concentrations, measured by chemiluminescence, and clinical parameters of low cardiac output syndrome. Results: Twelve children were allocated to remote ischemic preconditioning, and 10 children were allocated to the control group. Demographic data and Risk Adjustment for Congenital Heart Surgery 1 classification were comparable in both groups. Remote ischemic preconditioning group had lower postoperative values of N-terminal pro-B-type natriuretic peptide, but cardiac troponin I levels were not significantly different between groups. Interleukin-8 and 10 concentrations and I kappa B alpha gene expression were similar in both groups. Postoperative morbidity was similar in both groups; there were no postoperative deaths in either group. Conclusions: Late remote ischemic preconditioning did not provide clinically relevant cardioprotection to children undergoing cardiopulmonary bypass. (J Thorac Cardiovasc Surg 2012;144:178-83)

Coronary plaque rupture in patients with myocardial infarction after noncardiac surgery: Frequent and dangerous

Purpose: The pathophysiology of acute coronary syndromes (ACS) after noncardiac surgery is not established yet. Thrombosis over a vulnerable plaque or decreased oxygen supply secondary to anemia or hypotension may be involved. The purpose of this study was to investigate the pathophysiology of ACS complicating noncardiac surgery. Methods: Clinical and angiographic data were prospectively recorded into a database for 120 consecutive patients that had an ACS after noncardiac surgery (PACS), for 120 patients with spontaneous ACS (SACS), and 240 patients with stable coronary artery disease (CAD). Coronary lesions with obstructions greater than 50% were classified based on two criteria: Ambrose's classification and complex morphology. The presence of Ambrose's type II or complex lesions were compared between the three groups. Results: We analyzed 1470 lesions in 480 patients. In PACS group, 45% of patients had Ambrose's type II lesions vs. 56.7% in SACS group and 16.4% in stable CAD group (P < 0.001). Both PACS and SACS patients had more complex lesions than patients in stable CAD group (56.7% vs. 79.2% vs. 31.8%, respectively; P < 0.001). Overall, the independent predictors of plaque rupture were being in the group PACS (P < 0.001, OR 2.86; CI, 1.82-4.52 for complex lesions and P < 0.001, OR 3.43; CI, 2.1-5.6 for Ambrose's type II lesions) or SACS (P < 0.001, OR 8.71; CI, 5.15-14.73 for complex lesions and P < 0.001, OR 5.99; CI, 3.66-9.81 for Ambrose's type II lesions). Conclusions: Nearly 50% of patients with perioperative ACS have evidence of coronary plaque rupture, characterizing a type 1 myocardial infarction. (C) 2012 Elsevier Ireland Ltd. All rights reserved.

Strategies for Multivessel Revascularization in Patients with Diabetes

BACKGROUND In some randomized trials comparing revascularization strategies for patients with diabetes, coronary-artery bypass grafting (CABG) has had a better outcome than percutaneous coronary intervention (PCI). We sought to discover whether aggressive medical therapy and the use of drug-eluting stents could alter the revascularization approach for patients with diabetes and multivessel coronary artery disease. METHODS In this randomized trial, we assigned patients with diabetes and multivessel coronary artery disease to undergo either PCI with drug-eluting stents or CABG. The patients were followed for a minimum of 2 years (median among survivors, 3.8 years). All patients were prescribed currently recommended medical therapies for the control of low-density lipoprotein cholesterol, systolic blood pressure, and glycated hemoglobin. The primary outcome measure was a composite of death from any cause, nonfatal myocardial infarction, or nonfatal stroke. RESULTS From 2005 through 2010, we enrolled 1900 patients at 140 international centers. The patients' mean age was 63.1 +/- 9.1 years, 29% were women, and 83% had three-vessel disease. The primary outcome occurred more frequently in the PCI group (P=0.005), with 5-year rates of 26.6% in the PCI group and 18.7% in the CABG group. The benefit of CABG was driven by differences in rates of both myocardial infarction (P<0.001) and death from any cause (P=0.049). Stroke was more frequent in the CABG group, with 5-year rates of 2.4% in the PCI group and 5.2% in the CABG group (P=0.03). CONCLUSIONS For patients with diabetes and advanced coronary artery disease, CABG was superior to PCI in that it significantly reduced rates of death and myocardial infarction, with a higher rate of stroke. (Funded by the National Heart, Lung, and Blood Institute and others; FREEDOM ClinicalTrials.gov number, NCT00086450.)

Phosphorus Is Associated with Coronary Artery Disease in Patients with Preserved Renal Function

High serum phosphorus levels have been associated with mortality and cardiovascular events in patients with chronic kidney disease and in the general population. In addition, high phosphorus levels have been shown to induce vascular calcification and endothelial dysfunction in vitro. The aim of this study was to evaluate the relation of phosphorus and coronary calcification and atherosclerosis in the setting of normal renal function. This was a cross-sectional study involving 290 patients with suspected coronary artery disease and undergoing elective coronary angiography, with a creatinine clearance >60 ml/min/1.73 m(2). Coronary artery obstruction was assessed by the Friesinger score and coronary artery calcification by multislice computed tomography. Serum phosphorus was higher in patients with an Agatston score >10 than in those with an Agatston score <= 10 (3.63 +/- 0.55 versus 3.49 +/- 0.52 mg/dl; p = 0.02). In the patients with Friesinger scores >4, serum phosphorus was higher (3.6 +/- 0.5 versus 3.5 +/- 0.6 mg/dl, p = 0.04) and median intact fibroblast growth factor 23 was lower (40.3 pg/ml versus 45.7 pg/ml, p = 0.01). Each 0.1-mg/dl higher serum phosphate was associated with a 7.4% higher odds of having a Friesinger score >4 (p = 0.03) and a 6.1% greater risk of having an Agatston score >10 (p = 0.01). Fibroblast growth factor 23 was a negative predictor of Friesinger score ( p = 0.002). In conclusion, phosphorus is positively associated with coronary artery calcification and obstruction in patients with suspected coronary artery disease and preserved renal function.

The association between coronary artery calcification progression and loss of bone density in non-dialyzed CKD patients

Background: Coronary artery calcification (CAC) and low bone density are coexisting deleterious conditions commonly shared by chronic kidney disease (CKD) patients. In the present study, we aimed to investigate whether the progression of CAC was associated with overtime reduction in bone density in non-dialyzed CKD patients. Methods: This is a prospective study of 24 months including 72 non-dialyzed CKD patients Stages 2 - 4 (age 57.6 +/- 10.3 years, 62% male, 22% diabetics). CAC and vertebral bone density (VBD) were measured by computed tomography. Results: At baseline, 46% of the patients had CAC (calcified group) and calcification was not identified in 54% of the patients (non-calcified group). The calcified group was older, predominantly male, and had lower VBD in comparison to non-calcified group. CAC progression was observed only in the calcified group (91% of the patients increased calcium score). The multiple regression analysis revealed loss of VBD as the independent determinant of CAC progression in these patients. Conclusion: CAC progression was associated with loss of VBD in non-dialyzed CKD patients.

Clinical Usefulness of Coronary Angiography in Patients with Left Ventricular Dysfunction

Background: Performing a coronary angiography in patients with heart failure of unknown etiology is often justified by the diagnostic assessment of ischemic heart disease. However, the clinical benefit of this strategy is not known. Objective: To evaluate the prevalence of ischemic heart disease by angiographic criteria in patients with heart failure and reduced ejection fraction of unknown etiology, as well as its impact on therapy decisions. Methods: Consecutive outpatients with heart failure and systolic dysfunction, who had an indication for coronary angiography to clarify the etiology of heart disease were assessed from 1 January 2009 to December 31, 2010. Patients diagnosed with coronary artery disease, positive serology for Chagas disease, congenital heart disease, valve disease or patients undergoing cardiac transplantation were excluded from the analysis. The sample was divided into two groups according to the indication for catheterization. Group-1: Symptomatic due to angina or heart failure. Group-2: Presence of >= 2 risk factors for coronary artery disease Results: One hundred and seven patients were included in the analysis, with 51 (47.7%) patients in Group 1 and 56 (52.3%) in Group 2. The prevalence of ischemic heart disease was 9.3% (10 patients), and all belonged to Group 1 (p = 0.0001). During follow-up, only 4 (3.7%) were referred for CABG; 3 (2.8%) patients had procedure-related complications. Conclusion: In our study, coronary angiography in patients with heart failure and systolic dysfunction of unknown etiology, although supported by current guidelines, did not show benefits when performed only due to the presence of risk factors for coronary artery disease. (Arq Bras Cardiol 2012;98(5):437-441)

Echocardiographic and hemodynamic determinants of right coronary artery flow reserve and phasic flow pattern in advanced non-ischemic cardiomyopathy

Abstract Background In patients with advanced non-ischemic cardiomyopathy (NIC), right-sided cardiac disturbances has prognostic implications. Right coronary artery (RCA) flow pattern and flow reserve (CFR) are not well known in this setting. The purpose of this study was to assess, in human advanced NIC, the RCA phasic flow pattern and CFR, also under right-sided cardiac disturbances, and compare with left coronary circulation. As well as to investigate any correlation between the cardiac structural, mechanical and hemodynamic parameters with RCA phasic flow pattern or CFR. Methods Twenty four patients with dilated severe NIC were evaluated non-invasively, even by echocardiography, and also by cardiac catheterization, inclusive with Swan-Ganz catheter. Intracoronary Doppler (Flowire) data was obtained in RCA and left anterior descendent coronary artery (LAD) before and after adenosine. Resting RCA phasic pattern (diastolic/systolic) was compared between subgroups with and without pulmonary hypertension, and with and without right ventricular (RV) dysfunction; and also with LAD. RCA-CFR was compared with LAD, as well as in those subgroups. Pearson's correlation analysis was accomplished among echocardiographic (including LV fractional shortening, mass index, end systolic wall stress) more hemodynamic parameters with RCA phasic flow pattern or RCA-CFR. Results LV fractional shortening and end diastolic diameter were 15.3 ± 3.5 % and 69.4 ± 12.2 mm. Resting RCA phasic pattern had no difference comparing subgroups with vs. without pulmonary hypertension (1.45 vs. 1.29, p = NS) either with vs. without RV dysfunction (1.47 vs. 1.23, p = NS); RCA vs. LAD was 1.35 vs. 2.85 (p < 0.001). It had no significant correlation among any cardiac mechanical or hemodynamic parameter with RCA-CFR or RCA flow pattern. RCA-CFR had no difference compared with LAD (3.38 vs. 3.34, p = NS), as well as in pulmonary hypertension (3.09 vs. 3.10, p = NS) either in RV dysfunction (3.06 vs. 3.22, p = NS) subgroups. Conclusion In patients with chronic advanced NIC, RCA phasic flow pattern has a mild diastolic predominance, less marked than in LAD, with no effects from pulmonary artery hypertension or RV dysfunction. There is no significant correlation between any cardiac mechanical-structural or hemodynamic parameter with RCA-CFR or RCA phasic flow pattern. RCA flow reserve is still similar to LAD, independently of those right-sided cardiac disturbances.

Association between UCP2 A55V polymorphism and risk of cardiovascular events in patients with multi-vessel coronary arterial disease

Background UCP2 (uncoupling protein 2) plays an important role in cardiovascular diseases and recent studies have suggested that the A55V polymorphism can cause UCP2 dysfunction. The main aim was to investigate the association of A55V polymorphism with cardiovascular events in a group of 611 patients enrolled in the Medical, Angioplasty or Surgery Study II (MASS II), a randomized trial comparing treatments for patients with coronary artery disease and preserved left ventricular function. Methods The participants of the MASS II were genotyped for the A55V polymorphism using allele-specific PCR assay. Survival curves were calculated with the Kaplan–Meier method and evaluated with the log-rank statistic. The relationship between baseline variables and the composite end-point of cardiac death, acute myocardial infarction (AMI), refractory angina requiring revascularization and cerebrovascular accident were assessed using a Cox proportional hazards survival model. Results There were no significant differences for baseline variables according genotypes. After 2 years of follow-up, dysglycemic patients harboring the VV genotype had higher occurrence of AMI (p=0.026), Death+AMI (p=0.033), new revascularization intervention (p=0.009) and combined events (p=0.037) as compared with patients carrying other genotypes. This association was not evident in normoglycemic patients. Conclusions These findings support the hypothesis that A55V polymorphism is associated with UCP2 functional alterations that increase the risk of cardiovascular events in patients with previous coronary artery disease and dysglycemia.

Alveolar recruitment maneuver in refractory hypoxemia and lobar atelectasis after cardiac surgery: A case report

Abstract Objective This case report describes an unusual presentation of right upper lobe atelectasis associated with refractory hypoxemia to conventional alveolar recruitment maneuvers in a patient soon after coronary artery bypass grafting surgery. Method Results The alveolar recruitment with PEEP = 40cmH2O improved the patient’s atelectasis and hypoxemia. Conclusion In the present report, the unusual alveolar recruitment maneuver with PEEP 40cmH2O showed to be safe and efficient to reverse refractory hypoxemia and uncommon atelectasis in a patient after cardiac surgery.

Diagnosis and treatment of coronary artery disease in hemodialysis patients evaluated for transplant

We present a review of current strategies for the diagnosis and treatment of coronary artery disease (CAD) in patients with advanced chronic kidney disease who are on the waiting list for transplants, based on data from the literature and originated from a single-center cohort of 1,250 patients with maximum follow-up of 12 years. We discuss the best way to select patients to be tested for CAD, how to choose the more adequate screening test for CAD and cardiovascular disease, how to select patients for invasive treatment studies and how to treat patients with significant CAD. We also suggest new research avenues to be explored to resolve some problems in this area.

Influência da posição do dreno pleural na função pulmonar de pacientes submetidos à revascularização do miocárdio

JUSTIFICATIVA E OBJETIVOS: Estudo longitudinal, prospectivo, aleatório e encoberto para avaliar a influência do local de inserção do dreno pleural, de PVC atóxico, na função pulmonar e na dor pós-operatória dos pacientes submetidos à revascularização do miocárdio nos três primeiros dias pós-cirúrgicos e logo após a retirada do dreno. PACIENTES E MÉTODOS: Trinta e seis pacientes escalados para cirurgia eletiva de revascularização do miocárdio, com uso de circulação extracorpórea (CEC), em dois grupos: grupo SX (dreno subxifoide) e grupo IC (dreno intercostal). Feitos registros espirométricos, da gasometria arterial e da dor. RESULTADOS: Trinta e um pacientes analisados, 16 no grupo SX e 15 no grupo IC. O grupo SX apresentou valores espirométricos maiores do que o grupo IC (p < 0,05) no pós-operatório (PO), denotando menor influência do local do dreno na respiração. A PaO2 arterial no segundo PO aumentou significantemente no grupo SX quando comparada com o grupo IC (p < 0,0188). A intensidade da dor no grupo SX, antes e após a espirometria, era menor do que no grupo IC (p < 0,005). Houve aumento significativo dos valores espirométricos em ambos os grupos após a retirada do dreno pleural. CONCLUSÃO: A inserção do dreno na região subxifoide altera menos a função pulmonar, provoca menos desconforto e possibilita uma melhor recuperação dos parâmetros respiratórios.