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To determine the impact of left anterior descending-competitive flow (LAD-CF) on distal coronary flow (LAD-DF) and on left internal mammary artery-graft flow (LIMA-GF), we performed a quantitative blood-flow analysis in a swine model of a LIMA-to-LAD coronary artery bypass graft (CABG). In six swine, a LIMA-to-LAD CABG was performed. LAD blood-flow was measured bilaterally to the LIMA-to-LAD anastomosis, in the LIMA and in the pulmonary artery (cardiac output, CO) along with the LIMA pulsatility index (LIMA-PI) and the left ventricular pressure (LVP). PreCABG measurements were followed by postCABG measurements at five levels of LAD-CF: 100%, 75%, 50%, 25% and 0% after gradually snaring down a snare placed proximally of the LAD-CF flow-probe. PreCABG CO and LVP remained unchanged postCABG. LAD-DF was reduced significantly postCABG (-33%, P<0.0001). Reduction of the LAD-CF (at 75%, 50%, 25% and 0%) resulted in significant increase of LIMA-GF (+38%, +63%, +113%, +225%, P<0.036 at all LAD-CF levels), reduced PI (6.8, 5.7, 4.1, 3.1, 2.5) with simultaneous increase of LAD-DF (+8%, P=NS, +8%, P=NS, +17%, P=NS, +50%, P=0.0044). Decreased LAD-CF resulted in increased LAD-DF, increased LIMA-GF and decreased LIMA-PI. To the best of our knowledge, this is the first study where blood-flow was directly and simultaneously measured in all the components of the LIMA-to-LAD anastomosis.

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OBJECTIVE: : To determine the hemodynamic effect of an off-pump apicoaortic valved graft (AAVG) implantation, we performed a quantitative coronary flow analysis in a swine model of severe aortic stenosis. METHODS: : In 10 swine, cardiac output, coronary flow, right common carotid artery flow, and internal mammary artery flow were measured along with left and right ventricular pressures and aortic and pulmonary artery pressures. A novel AAVG was implanted off-pump on the left ventricular (LV) apex using a specially designed implantation tool and anastomosed to the descending thoracic aorta. Aortic flow was measured proximally and distally of the AAVG-to-descending thoracic aorta anastomosis. After AAVG implantation, epicardial echo confirmed occlusion of the LV outflow tract by a valvuloplasty balloon. Baseline simultaneous measurements of all parameters were repeated after AAVG implantation and intravenous Dobutamine administration. RESULTS: : The AAVG was implanted without any blood loss. After AAVG implantation and LV outflow tract occlusion, the aortic flow proximal to the AAVG-to-descending thoracic aorta anastomosis changed from antegrade (1508 ± 435 mL/min) to retrograde (-529 ± 241 mL/min, P < 0.001). All other measured parameters remained unchanged compared with baseline. After intravenous Dobutamine administration, LV pressure increased from 88 ± 20 to 184 ± 36 mm Hg (+209%, P < 0.0001) and coronary flow increased from 75 ± 34 to 193 ± 90 mL/min (+257%, P = 0.001). CONCLUSIONS: : The off-pump implantation of an AAVG is bloodless, safe, reproducible and has no negative impact on coronary flow and hemodynamics. In addition, to the best of our knowledge, this is the first study where blood flow in all coronary arteries was measured simultaneously during an AAVG implantation.

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We present a patient with Lady Windermere syndrome after coronary bypass operation. To avoid the sternal pain that occurred after every cough episode, this patient used to receive large doses of antitussive drugs. In a poorly drained lung, this usage leads to the development of regions of colonization with Mycobacterium avium complex. It is concerning that the lack of diagnosis for 18 months in this patient occurred because of the insidious symptoms that mimic bronchitis. This case emphasizes how important it is for patients after a median sternotomy to receive adequate analgesic and physiotherapeutic support in order to avoid chronic inflammation and infection of the lungs.

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BACKGROUND AND OBJECTIVES: Epinephrine has been the mainstay drug of choice for cardiac resuscitation for more than 30 years. Its vasopressor effects favoring initial resuscitation point to its beta-adrenergic action. However, its beta-adrenergic actions may have detrimental effects. The aim of the present experimental study was to evaluate the efficiency of coadministration of Esmolol, an ultra-short-acting beta-blocker, and of epinephrine in a swine model of cardiac arrest. MATERIALS AND METHODS: Fourteen pigs (19 +/- 2 Kg) were anesthetized and instrumented. Ventricular Fibrillation (VF) was produced electrically. After induction of VF, the animals were left untreated for 5 minutes. Animals were randomized into two groups, control and study group. Six animals were used in the control group, and 8 in the study group. The control group received 10 ml of normal saline via a peripheral vein, while the study group received 0.4 mg/kg Esmolol in 10 ml dilution. Epinephrine was administered to all animals after the first unsuccessful defibrillation set, and all animals received standardized Advanced Life Support. RESULTS: Seven animals (87.5%) restored cardiac rhythm compatible with a pulse in the Esmolol group, compared to 2 animals (33.3%) in the control group (p = 0.018). The average time until restoration of circulation was 16 +/- 3.2 minutes in our control group and 12.8 +/- 1.4 minutes in Esmolol group (p = 0.059). Coronary perfusion pressure (CPP) was significantly higher in the Esmolol group. CONCLUSIONS: Esmolol improves significantly the outcome of cardiopulmonary resuscitation and the average time of restoration of circulation, while in the proposed dosage does not alter the CPP at the beginning of CPR. However, it augments CPP from the sixth minute of CPR and afterwards.

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The use of swine in cardiopulmonary resuscitation (CPR) research has increased in the last decades. Landrace-Large White (LLW) swine are a farm breed of pigs. The aims of the present study were to describe the baseline hemodynamics of this breed and to demonstrate that it is suitable for CPR research. The systolic and diastolic pressures of the descending aorta (mean +/- 1 standard deviation; n = 29) were 111.72 +/- 13.61 and 79.03 +/- 12.08 mm Hg, respectively, whereas the mean systolic and diastolic pressures of the left ventricle were 108.97 +/- 12.06 and 8.88 +/- 1.81 mm Hg, respectively. The mean pressures of the right atrium were 10.93 +/- 1.36 mm Hg (systolic) and 4.10 +/- 1.01 mm Hg (diastolic), whereas the value obtained by using near-infrared spectroscopy to determine brain regional oxygen saturation was 64.55% +/- 3.88%. LLW can be considered a suitable breed for CPR research because of the close similarity of its hemodynamic values to those of humans.

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