Paolo Nardi

Opening and closing characteristics of the aortic valve after valve-sparing procedures using a new aortic root conduit

BACKGROUNDnThe durability of aortic valve-sparing procedures is negatively affected by increased leaflet stress in the absence of normally shaped sinuses of Valsalva. We compared valve motion after remodeling procedures using a standard conduit and a specifically designed aortic root conduit.nnnMETHODSnEchocardiographic studies of the aortic valve dynamics were performed in 14 patients after remodeling of the aortic root (7 standard conduits, group A; 7 new conduits, group B) and in 7 controls (group C). Opening and closing leaflet velocities and percent of slow closing leaflet displacement were measured. Root distensibility and the pressure strain of the elastic modulus were measured at all root levels.nnnRESULTSnRoot distensibility and the pressure strain of the elastic modulus were different in group A and B only at the sinuses (p < 0.001). Opening and closing leaflet velocities were not different among groups. Slow closing leaflet displacement was markedly more evident in group B patients (24.2%+/-1.9% versus 2.5%+/-1.9% in group A, p < 0.001) and similar to controls (22.1%+/-7.9%).nnnCONCLUSIONSnThe new conduit guarantees dynamic features of the aortic valve leaflets superior to those obtained with standard conduits and more similar to normal subjects.

Analysis of valve motion after the reimplantation type of valve-sparing procedure (David I) with a new aortic root conduit.

BACKGROUNDnThe reimplantation type of valve-sparing procedure does not allow proper reconstruction of the sinuses of Valsalva. We assessed the valve motion after a reimplantation type (David I) of valve-sparing procedure using a new Dacron conduit that incorporates sinuses of Valsalva.nnnMETHODSnNine consecutive patients undergoing an aortic valve-sparing procedure using the new conduit were studied using two-dimensional transesophageal echocardiography shortly (2 +/- 1 months) after operation to determine root distensibility, expressed as percent change in radius and as pressure strain of the elastic modulus. Next, monodimensional view was used to assess valve motion in its various phases (rapid valve opening velocity, slow closing leaflet displacement, rapid valve closing velocity, maximal leaflet displacement, and leaflet displacement before valve closure). Seven healthy individuals served as control subjects.nnnRESULTSnRoot distensibility was reduced at the level of the annulus and sinotubular junction but was similar to control subjects at the level of the sinuses (percent change in radius, 4.1% +/- 0.8% versus 4.5% +/- 1.2%; pressure strain of the elastic modulus, 1,286 +/- 674 g/cm2 versus 1,195 +/- 628 g/cm2). Rapid valve opening (69 +/- 34.4 cm/s versus 51 +/- 11.9 cm/s) and closing (47.6 +/- 16 cm/s versus 36.4 +/- 9 cm/s) velocity as well as slow closing leaflet displacement (24% +/- 4.7% versus 22.1% +/- 7.9%), maximal leaflet displacement (20.1 +/- 4 mm versus 22.7 +/- 1.9 mm), and leaflet displacement before valve closure (15.2 +/- 3 mm versus 17.6 +/- 0.8 mm) were similar to control subjects.nnnCONCLUSIONSnThe new aortic root conduit used in a reimplantation type of valve-sparing procedure allows the anatomic reconstruction of the aortic root with leaflet motion similar to that of normal subjects.

Coronary flow reserve early and late after minimally invasive coronary artery bypass grafting in patients with totally occluded left anterior descending coronary artery

BACKGROUNDnThe impairment of flow reserve of the left anterior descending coronary artery in the early postoperative period in patients receiving a left internal thoracic artery graft has been related to the effects of cardiopulmonary bypass. Indeed, the late improvement in flow has been attributed to a late increase in left internal thoracic artery diameter.nnnMETHODSnWe evaluated 12 patients who underwent minimally invasive direct coronary artery bypass surgery with the internal thoracic artery used to graft an occluded left anterior descending artery without extracorporeal circulation. Early and 6 months after the operation, patients underwent a second angiogram of the left internal thoracic artery graft and assessment of coronary flow reserve by use of an intracoronary 0.014-inch Doppler guide wire.nnnRESULTSnAt the late study, coronary flow reserve had increased compared with the early postoperative data from 1.8 +/- 0.4 (standard deviation) to 2.5 +/- 0.6 (P =.002) because of a significant decrease in baseline averaged peak velocity (32.4 +/- 6.2 vs 21.3 +/- 6.4 cm/s, P =.002), whereas the hyperemic values were similar (51 +/- 6 vs 53.7 +/- 21.9 cm/s, P =.6). The diameters of the thoracic artery (2.1 +/- 0.3 vs 2.2 +/- 0.3 mm, P =. 7) and the left anterior descending coronary artery (1.8 +/- 0.1 vs 1.8 +/- 0.2 mm, P =.5), as well as myocardial oxygen consumption (106 +/- 14 vs 101 +/- 16 mm Hg. beats/min. 10(-2), P =.5), were unchanged.nnnCONCLUSIONSnOur findings suggest that the late improvement in coronary flow reserve is independent of the diameter of the graft and probably reflects an early distal coronary vessel dysfunction, which normalizes with time.

p53 codon 72 polymorphism and coronary artery disease: evidence of association with left ventricular ejection fraction.

Introduction:Recently, there has been a surge of interest on the possible relationship between p53 polymorphism and coronary atherosclerosis. The authors have investigated the possible association of p53 codon 72 polymorphism with left ventricular ejection fraction (LVEF) in subjects with and without coronary artery disease (CAD). Methods:The authors have studied 198 subjects admitted consecutively to Valmontone Hospital for CAD and 129 subjects admitted for cardiovascular diseases without CAD. Fifty-nine subjects admitted for CAD to Division of Cardiac Surgery of Tor Vergata University were also studied. All subjects were from the white population. The p53 polymorphism was evaluated using the restriction fragment length polymorphism polymerase chain reaction. Results:p53 codon 72 polymorphism is a significant independent predictor of LVEF in subjects with CAD but not in subjects with cardiovascular disease without CAD. In subjects with CAD, LVEF is significantly lower in subjects carrying the *Pro variant than in *Arg/*Arg subjects. This effect is more evident in subjects with a positive history of infarction. Conclusions:Our study points to a significant relationship of p53 codon 72 polymorphism with cardiac function in subjects with CAD.