Obesity, Cardiac Remodeling, and Metabolic Profile: Validation of a New Simple Index beyond Body Mass Index.

AIM: The body mass index (BMI), the most used anthropometric index of obesity, has an important limitation, not taking into consideration the distribution of body fat. We developed a new simple index: the waist-corrected BMI (wBMI), calculated as waist circumference (WC) × BMI. The study aim was to assess the role of wBMI, compared to BMI, WC, and Waist-to-Height Ratio (WHtR) in predicting abnormal cardiac geometry, insulin resistance, increased arterial stiffness, and dyslipidemia. METHODS: This was a cross-sectional study that included 805 patients referred to our Department of Preventive Cardiology for risk factors evaluation and treatment. Eleven echographic and laboratory parameters were determined, and receiver operating characteristic (ROC) curves were derived. Areas under ROC curves (AUC) were used to assess the accuracy of the four indexes to identify unfavorable characteristics. RESULTS: There were 29% overweight, 59% obese, and 77% hypertensive patients. Of 11 echographic and laboratory parameters, wBMI, BMI, WHtR, and WC had the largest AUC for identifying 3, 1, 6, and 1 parameters, respectively, but with overlapping 95% confidence intervals. wBMI had the largest AUC for increased arterial stiffness and insulin resistance; also, it was superior to BMI for increased left atrial volume, relative wall thickness, and triglyceride level. CONCLUSIONS: In a large population with a high prevalence of obesity and hypertension, all four indexes were associated with unfavorable characteristics. wBMI has the theoretical advantage of taking into account simultaneously the global fat mass and distribution and might be useful for a better cardiovascular risk assessment.

Impact of metabolic syndrome traits on cardiovascular function: should the Adult Treatment Panel III definition be further stratified?

AIMS: The aims of the study were to evaluate whether a further classification of metabolic syndrome according to the number of traits (based on the Adult Treatment Panel III definition) could better explain the impact on cardiovascular remodeling and function, and to assess the role of single metabolic syndrome components in this regard. METHODS: We studied by echocardiography and carotid ultrasound 435 asymptomatic patients with metabolic syndrome. Patients with coronary artery disease or more than mild valvular heart disease were excluded. Carotid stiffness index (ß) was measured using a high-resolution echo-tracking system. Patients with metabolic syndrome were divided into two groups: metabolic syndrome with three traits (Gr.1) and metabolic syndrome with four or five traits (Gr. 2). RESULTS: Patients in Gr. 2 had higher left ventricular mass index (P < 0.001), left ventricular end-diastolic volume index (P = 0.029), left atrial volume index (P = 0.002), E/e' ratio (P = 0.002), intima-media thickness (P = 0.031), and prevalence of plaques (P = 0.01) than patients in Gr. 1. Left ventricular ejection fraction was similar in both groups. The mean carotid ß index tended to be higher in Gr. 2. Considering metabolic syndrome traits separately, in an age-corrected multivariate analysis, abdominal obesity was found to have the strongest association with cardiac structure and carotid artery atherosclerosis and stiffness. CONCLUSION: An increasing number of metabolic syndrome traits had a significantly worse impact on cardiac remodeling and function and carotid artery atherosclerosis. Abdominal obesity showed the strongest association with cardiac structure, carotid artery stiffness, and intima-media thickness. Prospective studies are needed to evaluate whether a new classification of metabolic syndrome using the number of traits could add prognostic information.

Cardiac structure and function and insulin resistance in morbidly obese patients: does superobesity play an additional role?

OBJECTIVE: To evaluate the impact of superobesity, defined as body mass index (BMI) ≥50, on cardiac structure and function. METHODS: Using echocardiography, we studied 198 asymptomatic patients (mean age 48 ± 13 years, 29.3% were men) with a BMI ≥40. Insulin resistance was measured using the Homeostasis Model Assessment of insulin resistance (HOMA-IR). Patients were divided into 2 groups: morbidly obese (BMI ≥40 and <50; n = 160) and superobese (BMI ≥50; n = 38). RESULTS: There were no significant differences in age, gender, hypertension and diabetes between groups. Superobese patients had higher LV mass (66.0 ± 14.7 vs. 59.9 ± 11.9 g/m(2.7), p = 0.007), left ventricular (LV) end-diastolic (33.8 ± 7.7 vs. 31.5 ± 7.1 ml/m(2.7), p = 0.041) and end-systolic (12.2 ± 3.6 vs. 10.9 ± 2.8 ml/m(2.7), p = 0.016) volumes, left atrial volume (13.8 ± 4.5 vs. 12.2 ± 3.9 ml/m(2.7), p = 0.029), peak velocity of transmitral flow in early diastole/early diastolic peak myocardial velocity ratio (9.1 ± 2.6 vs. 8.2 ± 2.2, p = 0.03) and HOMA-IR (9.7 ± 7.3 vs. 7.3 ± 6.5, p = 0.047). LV ejection fraction was similar. CONCLUSIONS: Superobesity is associated with insulin resistance and a worse impact on cardiac remodeling and LV diastolic function than morbid obesity. Prospective studies are needed to evaluate whether such further classification of morbid obesity could stratify the cardiovascular risk in these patients more accurately.

Incremental value of arterial stiffness over traditional risk factors in predicting subclinical cardiovascular remodeling in patients with moderate chronic renal failure.

Cardiovascular remodeling in chronic kidney disease (CKD) is responsible for the high mortality found in this condition. A total of 89 consecutive outpatients with stage III CKD and 52 patients with stage II CKD with similar degree of traditional atherosclerotic risk factors underwent routine echocardiographic and carotid Doppler examination, evaluating vascular and cardiac remodeling (intima-media thickness [IMT] and left ventricular mass index [LVMi]), and its relation with arterial stiffness, determined in the same examination, using an echo-tracking technique. Also the absolute values of LVMi and IMT were statistically similar between the 2 groups, their determinants were completely different, only in stage III the markers of renal impairment and arterial stiffness being independent predictors of cardiac and vascular modifications. We concluded that macroanatomical measurements do not fully describe cardiovascular remodeling in this setting. Arterial stiffness echo-tracking derived could add valuable information, being an easy-to-perform parameter during a routine examination.

[Safety and effectiveness of dual chamber pacing in patients over 80 years of age with previous episodes of paroxysmal atrial fibrillation]. / Utilità ed appropriatezza della stimolazione bicamerale nell'ultraottantenne con storia di fibrillazione atriale parossistica.

BACKGROUND: Dual chamber pacing (DDD) in the elderly is still a controversial issue because of its short life expectancy and the risk of atrial fibrillation. The aim of the study was 1) to evaluate the cumulative survival and the events capable of modifying it, 2) to evaluate the stability of sinus rhythm, and 3) to try to identify patients who are at a higher risk of developing permanent atrial fibrillation after DDD implantation. We evaluated clinical, electrophysiological and pacing parameters at the time of implantation. METHODS: We examined retrospectively a group of 135 consecutive patients who were > 80 years old and who were treated with DDD in the last decade. RESULTS: At the time of evaluation (mean 33.51 +/- 27.10 months, range 4-148 months) after DDD implantation, 72% of patients were still alive. Sinus rhythm was documented in 96 (71%) patients (group A). Thirty-nine (29%) patients (group B) developed atrial fibrillation after a mean period of 28.56 +/- 30.9 months (range 1-125 months). The right atrial endocavitary signal amplitude was lower in group B compared to that observed in group A (2.6 +/- 1.16 vs 3.27 +/- 1.91 mV). The pacing and sensing atrioventricular delay were not statistically different in both groups. The minimum heart rate was higher in patients who developed atrial fibrillation (64.53 +/- 7.7 vs 67.7 +/- 5.72 b/min respectively in group A and in group B, p = 0.02). Group B patients had a higher rate of atrial fibrillation pre-implantation episodes. The incidences of sick sinus disease and of atrioventricular nodal disease were similar in both groups. CONCLUSIONS: In elderly patients the benefits of DDD are maintained for a long period of time before the development of atrial fibrillation. Episodes of atrial fibrillation prior to DDD, apart from sinus dysfunction alone, are predictive of the development of a permanent atrial fibrillation. Permanent atrial fibrillation does not seem to reduce life expectancy. A higher minimum heart rate does not seem to prevent atrial fibrillation. The capability of recording a right atrial signal amplitude > 3 mV seems to identify those patients with a lower risk of developing atrial fibrillation.

Transesophageal electrical cardioversion of persistent atrial fibrillation: a new approach for an old technology.

BACKGROUND: Low energy intracardiac cardioversion may be considered the elective, alternative method for the acute restoration of sinus rhythm when direct current cardioversion fails or is contraindicated. Transesophageal cardioversion is a further alternative method for the recovery of sinus rhythm and obviates the potential complications of the low energy intracardiac cardioversion venous approach. METHODS: The present prospective study including 30 patients (21 males, 9 females, mean age 65.1 years, range 52-76 years), with persistent atrial fibrillation (mean duration 4.3 months), was undertaken in order to further evaluate, with regard to transesophageal cardioversion: 1) the acute efficacy, 2) the patient acceptance of the procedure, 3) the preferable choice among direct current cardioversion, low energy intracardiac cardioversion and transesophageal cardioversion, 4) the time required to perform the procedure, 5) the incidence of complications, and 6) the persistence of sinus rhythm after 1 month. RESULTS: Sinus rhythm was acutely restored in 29 patients (96.7%). Discomfort induced by the electrical shock was minimal or mild in most patients (75.8%). Transesophageal cardioversion was usually preferred by patients who had been previously submitted to direct current cardioversion or low energy intracardiac cardioversion. The mean total time required to perform the procedure was 107.9 min. No complications related to the procedure occurred. In spite of adequate pharmacological prophylaxis of atrial fibrillation only 41.4% of patients were in sinus rhythm 1 month after successful transesophageal cardioversion. CONCLUSIONS: Transesophageal cardioversion may be considered a very effective, well accepted and non-time consuming procedure for the short-term restoration of sinus rhythm. The incidence of complications is low.