Plamen Panayotov

Adipoparacrinology - Vascular periadventitial adipose tissue (Tunica adiposa) as an example

Human adipose tissue is partitioned into two large depots (subcutaneous and visceral), and many small depots associated with internal organs, e.g. heart, blood vessels, major lymph nodes, pancreas, prostate gland and ovaries. Since the adipose ‘Big Bang’ led to the discovery of leptin (Zhang, Proenca, Maffei, Barone, Leopold and Friedman, Nature 1994;372:425–32), adipose tissue has been seen not merely as a lipid store, but as a secretory – endocrine and paracrine – organ, particularly in the pathogenesis of a number of diseases. Accordingly, two major sub‐fields of adipobiology have emerged, viz. adipoendocrinology and adipoparacrinology, the latter herein being illustrated by PAAT (periadventitial adipose tissue) in vascular walls. A long‐standing paradigm holds that the vascular wall consists of three coats, tunica intima, tunica media and tunica adventitia. It is now imperative that ‘to further elucidate vascular function, we should no longer, as hitherto, separate adventitia and PAAT from the vascular wall, but keep them attached and in place, and subject to thorough examination’ (Chaldakov, Fiore, Ghenev, Stankulov and Aloe, Int Med J 2000;7:43–9; Chaldakov, Stankulov and Aloe, Atherosclerosis 2001;154:237–8; Chaldakov GN, Stankulov IS, Fiore M, Ghenev PI and Aloe L, Atherosclerosis 2001;159:57–66). From the available data, we propose that it is time to rethink about vascular wall composition, and suggest that the PAAT may be considered the fourth and outermost vascular coat, hence, tunica adiposa (regarding the proximal segment of coronary artery, it is the innermost part of the EAT (epicardial adipose tissue) situated around the coronary adventitia). Its significance in the pathogenesis and therapy of CMDs (cardiometabolic diseases), particularly atherosclerosis and hypertension, requires further basic, translational and clinical studies.

Anomalous origin of left circumflex coronary artery from the right pulmonary artery in adult.

Anomalous coronary arteries occur in less than 2% of the general population. The left circumflex (LCx) arterys origin from the pulmonary artery as a cause of classic angina in adults is extremely uncommon. We report a case of ischemic heart disease due to an origin of the LCx artery from the right main pulmonary artery in a 33-year-old man. Successful surgical correction of this defect was performed with total cardiopulmonary bypass and cardioplegic arrest.

Left heart chambers reverse remodeling after combined CABG and mitral repair

Results The mean effective ejection fraction increased from 18 ± 6% to 39 ± 13% (p << 0.05) at the follow-up. Left ventricular end-systolic volume index decreased from 44 ± 24 ml/m2 to 39 ± 26 ml/m2 (p = 0.002). Significant left ventricular reverse remodeling (≥ 15% reduction of LVESVI) was observed in 55 % of all survivors. Recurrent IMR was detected in only 2.8% (2/71) of the evaluated patients. Left atrial volume index decreased from 43 ± 15 ml/m2 to 36 ± 14 ml/m2 (p = 0.000003) and left atrial reverse remodeling was significant for 57 % of all survivors.

Effect of isolated cabg on mild-to-moderate ischemic mitral regurgitation and cardiac remodeling

Results At follow-up 56 % of all survivors showed improvement in IMR grade, 32 % presented with the unchanged valve function and in only 12 % IMR grade was more severe than preoperative. Preoperative effective ejection fraction increased from 26 ± 8% to 32 ± 14% (p = 0.002) at the follow-up. Left ventricular end-systolic volume index (LVESVI) decreased from 35 ± 16 ml/m2 to 30 ± 14 ml/m2 (p = 0.001). Significant left ventricular reverse remodeling (≥ 15% reduction of LVESVI) was observed in 45 % of all survivors. In 21 % of all survivors significant left atrial reverse remodeling was present although mean left atrial volume index did not change significantly. Conclusions Isolated surgical revascularization improves the valve function in ischemic mitral regurgitation. It also triggers significant left ventricular reverse remodeling in half of the patients. It remains unclear how the persisting or advancing remodeling process seen in the other half changes the prognosis of these individuals.

Echocardiographic evaluation of changes in diastolic dysfunction after CABG surgery, effect of novel therapy with Ivabradine

Methods Two groups of patients with triple-vessel coronary disease were evaluated. Each group consisted of 15 patients,aged between 40 and 70, 70% being males and 30% females.The patients in both groups had similar systolic left ventricular function and some degree of diastolic dysfunction. Group I patients had standard postoperative medical treatment, and in Group II supplemental therapy with Ivabradine 5 – 7.5 mg bid was added early after surgery. Patients with concomitant valvular and/or pericardial disease were excluded. The echocardiography was performed with M-mode and Two-dimensional examination, Pulsed wave Doppler imaging and Tissue Doppler imaging. The following echocadiographic criteria for diastolic dysfunction evaluation were used: LA dimension mm; LA Volum mL/m2; E/A; E m/s and A m/s; DTE ms; e’ cm/s and a’ cm/s; E/e’; Ar – A dur ms (Ar = duration of pulm. venous A-wave, Adur=duration of mitral inflow (Ar = duration of pulm. venous A-wave, Adur = duration of mitral inflow A-wave); IVRT ms; S/D. Patients were examined before, 7 days and 3 months after surgery. Results We observed a tendency towards normalization of e’ wave, and E/e’ in Group II. Reduced Ar-Adur was found as well. Changes in DTE and LA volume were another tendency, found in Group II.Such tendencies are not observed in Group I. Significant changes of variables within the Ivabradine treated group, reaching the normal range, are shown in graphics.

Adipoparacrinology of Atherosclerosis: Evidence Updated

Abstract: Recently, the secretory - endocrine, paracrine and autocrine - phenotype of adipose tissue, consisting of adipo-cytes, stromovascular cells and immune cells, has increasingly been recognized. In humans, adipose tissue is partitioned into two large depots (subcutaneous and visceral) and many small depots associated with heart, blood vessels, major lymph nodes, pancreas, prostate gland, ovaries. Accordingly, two major subfields of adipobiology have emerged, adi-poendocrinology (studying the endocrine activity of adipose tissue) and adipoparacrinology (studying the paracrine activ-ity of adipose tissue). Traditional concept of the pathogenesis of atherosclerosis focuses on intimal surface, where endo-thelial dysfunction expressed by an “inside-out” inflammatory process triggers the formation of atherosclerotic plaque. The present short review highlights evidence for the possible role of dysfunctional paracrine activity of epicardial adipose tissue and of periadventitial adipose tissue in an “outside-in” pathway in the development of coronary and peripheral athe-rosclerosis, respectively. Such a paradigm may have various therapeutic applications including in coronary artery bypass surgery.