Experimental & Clinical Cardiology最新文献

Objectives: In the surgical treatment of acute aortic dissection, tissue glues are widely used to reinforce the adhesion between the dissected aortic layers. A new inflatable balloon device was developed to compress the dissected aortic wall during gluing to increase adhesion between the dissected layers. The present study used an ex vivo experimental animal model to test the hypothesis that this device is effective when gluing the true and false channels of dissected aortas.

Methods: In the ex vivo experimental model, aortic dissection was simulated surgically on 12 fresh bovine aorta samples. In six samples (group I), the inflatable balloon device was inserted into the aorta to reinforce and fuse the dissected layers during gluing. The other six fresh bovine aortic samples (group II) were compressed between the surgeon's fingers during gluing. Aortic samples were evaluated and compared macroscopically and histologically.

Results: In group I, adhesion between the dissected layers was easily achieved during gluing. All false cavities were perfectly closed, with no deleterious effects related to the device. In group II, the adhesion between the dissected layers was not complete and some false cavities remained patent.

Conclusions: The inflatable balloon device can increase the adhesive effect of tissue glues via homogenous compression of the dissected aortic layers. In addition, the balloon can prevent distal embolization of the glue.

A 62-year-old woman with multiple myeloma and light-chain amyloidosis with significant heart involvement developed an in-hospital cardiac arrest. After cardiopulmonary resuscitation, a stable sinus rhythm without any cerebral damage was restored, and the patient was admitted to the coronary care unit. A cardioverter-defibrillator was implanted, and it successfully intervened in two sustained ventricular tachycardia episodes and one ventricular fibrillation episode, which were recorded during hospitalization. After achieving discrete cardiac compensation, the patient was transferred to the emergency medicine department where she underwent chemotherapy for multiple myeloma. The patient died 40 days after admission from refractory heart failure. In the literature, there are studies that describe the use of cardioverter-defibrillator implantation in cardiac amyloidosis; however, at present, there is no evidence of a beneficial effect on survival with the use of this intervention. A high index of suspicion for amyloid heart disease and early diagnosis are critical to improving outcomes.

Background: Few studies have assessed the prevalence of mixed dyslipidemia (MD) and the effectiveness of lipid-modifying therapy (LMT) for the treatment of abnormal levels of low-density lipoprotein cholesterol (LDL-C), triglycerides (TG) and high-density lipoprotein cholesterol (HDL-C) in Australian clinical practice.

Objective: To estimate the prevalence of MD in Australian patients undergoing LMT.

Methods: Patients 35 years of age and older undergoing LMT for ≥1 year were enrolled from nine general practice and cardiologist/endocrinologist outpatient clinics in Australia between April 2007 and May 2008. Lipid levels, including LDL-C, HDL-C and TG levels, were prospectively collected at the enrollment date and from patient records one year before LMT was initiated. Normal lipid levels were assessed according to Australian guidelines. Multivariate logistic regression was used to evaluate predictors of normal lipid level attainment.

Results: Of 297 patients (mean age 60.1 years; 43% male), the prevalence of MD before LMT was 61%; 93% of patients had elevated LDL-C levels, 17% had low HDL-C levels and 62% had elevated TG levels. Following LMT (98.3% statins), 31% of patients had MD. The prevalence of elevated LDL-C levels, low HDL-C levels and elevated TG levels were 44%, 21% and 42%, respectively. Baseline lipid levels were significant predictors of attainment of normal LDL-C levels (OR 0.42 [95% CI 0.27 to 0.63]) and TG levels (OR 0.26 [95% CI 0.16 to 0.45]).

Conclusion: Among Australian patients primarily treated with statins, nearly one-third had MD despite LMT. LMT considerably improved LDL-C goal attainment; however, a large proportion of patients did not achieve normal HDL-C and TG levels. Patients may benefit from a more comprehensive approach to lipid management that treats all three lipid risk factors, as suggested in clinical guidelines.

Objectives: To investigate the prevalence of subclinical thyroid dysfunction and the relationship between thyrotropin levels and cardiovascular risk factors in residents of the coastal area of China.

Methods: Atotalof4256individuals(mean[±SD]age50.51±14.24years; 2079 males, 2177 females,) were enrolled in the present study. Sex, blood pressure, body mass index, waist-to-hip ratio, serum levels of fasting glucose, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, uric acid and smoking status were measured. The relationship between thyrotropin levels and cardiovascular risk factors was analyzed.

Results: The overall prevalence of thyroid dysfunction was 11.07%. The prevalence of subclinical hypothyroidism (6.32%) was higher than that of hyperthyroidism (1.53%). The prevalence of thyroid dysfunction among female subjects was higher than that among male subjects (16.54% versus 5.34%, respectively; P<0.001). Significant differences were detected with respect to body mass index (P=0.026), waist-to-hip ratio (P<0.001), fasting glucose levels (P=0.001), total cholesterol levels (P=0.013), triglyceride levels (P=0.003) and smoking status according to different thyrotropin levels.

Conclusion: The prevalence of thyroid dysfunction was high in residents of China's coastal area. Significant differences were detected with regard to body mass index, waist-to-hip ratio, fasting glucose levels, total cholesterol levels, triglyceride levels and smoking status according to different thyrotropin levels.

Background: Double valve replacement for concomitant aortic and mitral valve disease is associated with substantial morbidity and mortality. Excellent results with valve repair in isolated mitral valve lesions have been reported; therefore, whether its potential benefits would translate into better outcomes in patients with combined mitral-aortic disease was investigated.

Methods: A retrospective observational study was performed involving 341 patients who underwent aortic valve replacement with either mitral valve repair (n=42) or double valve replacement (n=299). Data were analyzed for early mortality, late valve-related complications and survival.

Results: The early mortality rate was 11.9% for valve repair and 11.0% for replacement (P=0.797). Survival (± SD) was 67±11% in mitral valve repair with aortic valve replacement and 81±3% in double valve replacement at five years of follow-up (P=0.187). The percentage of patients who did not experience major adverse valve-related events at five years of follow-up was 83±9% in those who underwent mitral valve repair with aortic valve replacement and 89±2% in patients who underwent double valve replacement (P=0.412). Age >70 years (HR 2.4 [95% CI 1.1 to 4.9]; P=0.023) and renal dysfunction (HR 1.9 [95% CI 1.2 to 3.7]; P=0.01) were independent predictors of decreased survival.

Conclusions: In patients with double valve disease, both mitral valve repair and replacement provided comparable early outcomes. There were no significant differences in valve-related reoperations, anticoagulation-related complications or prosthetic valve endocarditis. Patient-related factors appear to be the major determinant of late survival, irrespective of the type of operation.

Quality assurance in atrial fibrillation is related to the appropriate use of anticoagulation. The CHADS2 score is widely used to determine which patients should or should not be anticoagulated. The authors hypothesized that as thromboembolic risk and, therefore, the CHADS2 score increases, so should the rate of anticoagulant prescription. The authors found a positive correlation between CHADS2 score and anticoagulant prescription (r=0.8) in a mini-survey. Although anticoagulant use at CHADS2 score = 0 was presumed to be very low, it was found to be higher than expected. This was readily explained by a group of low-risk patients being anticoagulated before cardioversion. Cardioverted patients were then examined as a group and it was found that the rate of rhythm control decreased with CHADS2 score (r= -0.89), a finding that has not been reported in the literature and may warrant further investigation.

Background/objective: The development of acute renal injury (ARI) is an important indicator of clinical outcomes after cardiac surgery. Neutrophil gelatinase-associated lipocalin (NGAL) has been certified as a predictive biomarker of hypoxic ARI. The present study aimed to determine the predictive role of NGAL in coronary bypass graft (CABG) surgery.

Method: A total of 72 consecutive patients undergoing elective CABG were enrolled in the study. NGAL levels were determined preoperatively and postoperatively after 6 h, 24 h and 72 h for all participants. The participants were then divided into two groups according to their preoperative creatinine levels (group I, creatinine 111.38 μmol/L to 361.55 μmol/L; group II, creatinine <111.38 μmol/L).

Results: There was no statistically significant difference between the groups according to their NGAL values (P>0.05), except at 6 h (P=0.045). Three patients required continuous hemodialysis. Comparison of the NGAL levels of these three patients with those of the other participants did not reveal any correlation with serum creatinine levels. In contrast, the NGAL levels were significantly lower in the continuous hemodialysis patients (1.9±1 ng/mL) compared with those of the other participants (22.6±12.8 ng/mL; P=0.001).

Conclusion: NGAL is one of the most frequently used biomarkers for ARI after cardiac operations, especially in younger patients. The participants in the present study were coronary artery disease patients and were, therefore, older than patients in previous reports. These results support the view that NGAL is not a relevant predictive factor for ARI in patients with CABG, including older patients.

Background: QT and P wave dispersion parameters can indicate abnormalities in autonomic nervous system and cardiac functioning.

Objectives: To determine QT and P wave dispersion in patients with major depressive disorder compared with healthy volunteers.

Methods: Fifty newly diagnosed patients with major depressive disorder and 50 age- and sex-matched healthy volunteers underwent 12-lead electrocardiography. QT interval, QT dispersion, heart rate-corrected QT dispersion and P wave dispersions were calculated manually by a blinded specialist.

Results: Groups were comparable in terms of age, sex, body mass index, smoking status, metabolic diseases and left ventricular ejection fraction. The major depressive disorder group had significantly higher QT dispersion (58.5±9.9 versus 41.7±3.8; P<0.001), heart rate-corrected QT dispersion (62.5±10.0 versus 45.2±4.3; P<0.001) and P wave dispersion (46.9±4.8 versus 41.5±5.1; P<0.001).

Conclusion: Increased QT dispersion, heart-rate corrected QT dispersion and P wave dispersion in major depressive disorder patients may be indicative of autonomic imbalance and increased risk of cardiac morbidity and mortality.

Background: Several imaging tests and biomarkers have been proposed for the identification of patients with unstable angina among those presenting to the emergency department with acute chest pain. Preliminary data suggest that ischemia-modified albumin (IMA) may represent a potentially useful biomarker in these patients.

Objective: To compare IMA and echocardiography in excluding unstable angina in patients with acute chest pain.

Methods: Thirty-three patients (mean [± SD] age 59.8±10.8 years; 28 men) presenting to the emergency department with acute chest pain lasting <3 h suggestive of acute coronary syndrome, with normal or non-diagnostic electrocardiograms, and creatine kinase MB and troponin levels within the normal range, were included in the present study.

Results: After further diagnostic evaluation, five patients (15.2%) were diagnosed with unstable angina. The sensitivity, specificity, positive predictive value and negative predictive (NPV) value of echocardiography for diagnosing unstable angina was 60.0%, 89.3%, 50.0% and 92.6%, respectively. The area under the ROC curve for diagnosing unstable angina based on the serum IMA levels was 0.193 (95% CI 0.047 to 0.339; P<0.05). Based on ROC curve analysis, serum IMA levels ≥31.95 IU/mL yielded the optimal combination of sensitivity and specificity for diagnosing unstable angina. The sensitivity, specificity, positive predictive value and NPV of serum IMA levels ≥31.95 IU/mL for diagnosing unstable angina was 40.0%, 28.6%, 9.1% and 72.7%, respectively.

Conclusions: Measurement of serum IMA levels appears to represent a useful tool for excluding unstable angina in patients presenting to the emergency department with acute chest pain. Moreover, IMA shows an NPV that is comparable with echocardiography.

Background: Peak oxygen consumption (VO2) is the gold standard measure of cardiorespiratory fitness and a reliable predictor of survival in chronic heart failure patients. Furthermore, any form of physical training usually improves cardiorespiratory fitness, although the magnitude of improvement in peak VO2 may vary across different training prescriptions.

Objective: To quantify, and subsequently rank, the magnitude of improvement in peak VO2 for different physical training prescriptions using data from published meta-analyses and randomized controlled trials.

Methods: Prospective randomized controlled parallel trials and meta-analyses of exercise training in chronic heart failure patients that provided data on change in peak VO2 for nine a priori comparative analyses were examined.

Results: All forms of physical training were beneficial, although the improvement in peak VO2 varied with modality. High-intensity interval exercise yielded the largest increase in peak VO2, followed in descending order by moderate-intensity aerobic exercise, functional electrical stimulation, inspiratory muscle training, combined aerobic and resistance training, and isolated resistance training. With regard to setting, the present study was unable to determine whether outpatient or unsupervised home exercise provided greater benefits in terms of peak VO2 improvment.

Conclusions: Interval exercise is not suitable for all patients, especially the high-intensity variety; however, when indicated, this form of exercise should be adopted to optimize peak VO2 adaptations. Other forms of activity, such as functional electrical stimulation, may be more appropriate for patients who are not capable of high-intensity interval training, especially for severely deconditioned patients who are initially unable to exercise.