Flavio Cerasuolo

Risk factors for pacemaker implantation following aortic valve replacement: a single centre experience

Objective: To identify perioperative clinical predictors of permanent pacemaker implantation following aortic valve replacement. Design and patients: Prospective cohort study on 276 patients submitted for aortic valve replacement: 267 patients (mean (SD) age, 57.5 (14) years) with no conduction disturbances, and nine patients (67.7 (5) years) with severe conduction disturbances requiring permanent pacing; 65 perioperative variables (38 preoperative, eight intraoperative, and 19 postoperative) were considered. Results: Nine patients (3.2%) had irreversible second or third degree atrioventricular (AV) block requiring permanent pacing. Risk factors for permanent pacing identified by univariate analysis were: preoperative: additional valvar disease, aortic regurgitation, myocardial infarction, pulmonary hypertension, anaemia, use of digitalis; intraoperative: cardiac arrest; postoperative: cardiac arrest, conduction disturbances, electrolytic imbalance, angiotensin converting enzyme inhibitor use. Multivariate logistic regression analysis identified preoperative aortic regurgitation (p < 0.005; odds ratio (OR) 6.6, 95% confidence interval (CI) 1.6 to 12.2), myocardial infarction (p < 0.0005; OR 15.2, 95% CI 6.3 to 19.9), pulmonary hypertension (p < 0.005; OR 12.5, 95% CI 3.2 to 18.3), and postoperative electrolyte imbalance (p < 0.01; OR 4.5, 95% CI 1.3 to 6.4). Conclusions: Irreversible AV block requiring permanent pacemaker implantation is an uncommon condition following aortic valve replacement. Previous aortic regurgitation, myocardial infarction, pulmonary hypertension, and postoperative electrolyte imbalance should be considered in order to identify patients at increased risk for advanced AV block.

Prosthetic valve obstruction: thrombolysis versus operation.

An acute obstruction is a life-threatening complication of mechanical valve prostheses, and is caused by the formation of fresh clot or fibrous tissue overgrowth, or both. Accurate selection of the most appropriate treatment for a particular patient is mandatory. From January 1991 to July 1992, 28 cases of prosthetic thrombosis were managed. Twenty patients underwent surgical treatment, with one operative death, and 8 patients were treated with thrombolysis using recombinant tissue-type plasminogen activator (rt-PA). The criteria for using thrombolysis were (1) the recent onset of symptoms, (2) transesophageal echocardiographic evidence of clots on the valve or cardiac chambers, and (3) preserved disc excursions. All patients who underwent thrombolysis had mechanical valves (two bileaflets, four tilting discs, and two ball valves); seven valves were in the mitral position and one was in the aortic. Symptoms of obstruction consisted of cardiac failure in 6 cases or thromboembolism in 5, or both. The mean interval between the onset of symptoms and the initiation of thrombolysis was 81 +/- 65 hours. After infusion of the rt-PA, normal valve function was restored in all patients, as documented by transesophageal echocardiography. No deaths or neurologic complications occurred; there was one episode of minor peripheral embolism. Thrombolysis using rt-PA may be the appropriate treatment in patients with primary thrombosis of mechanical valves, thereby avoiding the operation-related risks.

ROLE OF MYOFIBROBLASTS IN VASCULAR REMODELLING: FOCUS ON RESTENOSIS AND ANEURYSM

Myofibroblasts (MFs) are contractile cells deriving from a multiplicity of resident cells and/or circulating progenitors that are known to play a key role in wound healing. They were first discovered and analysed in the early 1970s in granulation tissue. Since their first identification, the role of MF and their mechanisms of differentiation have been highlighted in a number of diseases, including organ fibrosis and tumours, with particular attention devoted to the liver, kidney, and pulmonary fibrosis. The aim of this review is to summarize the current evidence for the role played by MFs in two frequent vascular diseases related to the remodelling of the vascular wall: the different forms of arterial restenosis and the most common forms of thoracic aortic aneurysm. The in-depth knowledge of the molecular pathways involved in MF differentiation, contraction, and survival/apoptosis could contribute to the identification of novel therapeutic strategies for anti-fibrotic and anti-remodelling therapy of vascular diseases in which these cells are involved.

Does antegrade blood cardioplegia alone provide adequate myocardial protection in patients with left main stem disease

BACKGROUND The optimum route for cardioplegia administration in patients with severe coronary disease is still under debate. This study compared clinical, echocardiographic, and biochemical results in patients with left main stem disease treated with 2 different strategies of myocardial protection. METHODS Between March 2000 and November 2002, 148 consecutive patients with left main stem disease undergoing coronary artery bypass grafting were divided into 2 groups according to the route of cardioplegia delivery: antegrade in 87 patients (group A) or antegrade followed by retrograde in 61 patients (group B). Electrocardiography, troponin I, MB-creatine kinase, and MB-creatine kinase mass were performed at 12, 24, 48, and 72 hours postoperatively. Echocardiography was performed preoperatively and before hospital discharge. Data were stratified in subgroups of patients with the following associated risk factors: left ventricular hypertrophy, diabetes, and right coronary stenosis. RESULTS Groups were homogeneous in preoperative and intraoperative variables, apart from the higher incidence of unstable angina and severity of left main stem disease in group B. Hospital deaths, intensive therapy unit and hospital stay, perioperative acute myocardial infarction, and intraaortic balloon pump support were similar in both groups. Postoperative recovery of left ventricle ejection fraction and wall motion score index did not differ between the 2 groups. However, postoperative atrial fibrillation was higher in group A (P =.015), especially in patients with diabetes (P <.0001). Troponin I was significantly higher in group A from postoperative hours 12 to 72 (P <.01), and the same pattern was observed in patients with diabetes (P <.001), critical right coronary stenosis (P <.001), and left ventricle hypertrophy (P <.001). CONCLUSION The combined route of intermittent blood cardioplegia allows better results in left main stem disease. Such data are confirmed even in risk subgroups.

Evolution in the treatment of mediastinitis: single-center experience.

This study aimed to evaluate our 30-year experience in the treatment of deep sternal wound infection after cardiac surgery. Between 1979 and 2009, deep sternal wound infections occurred in 200 of 22,366 (0.89%) patients who underwent sternotomy. The study population was divided into 3 groups. In group A (62 patients; 1979–1994), an initial attempt at conservative antibiotic therapy was the rule, followed by surgery in case of failure. In group B (83 patients; 1995–2002), the treatment was in 3 steps: wound debridement and closed irrigation for 10 days; in case of failure, open dressing with sugar and hyperbaric treatment; delayed healing and negative wound cultures mandated plastic reconstruction. In group C (2002–2009), the treatment was based on early surgical debridement, vacuum application, and reconstruction using pectoralis muscle flap. Hospital mortality in group A was significantly higher than that in groups B and C. Hospital stay, time for normalization of white blood cell count and C reactive protein, and time for defervescence were significantly shorter in group C. In our experience, early surgical debridement and vacuum application followed by plastic reconstruction provided a satisfactory rate of healing and a good survival rate.

A Starr-Edwards mitral prosthesis after 44 years of good performance.

The Starr-Edwards caged-ball prosthesis has been widely used to replace cardiac valves. The Model 6120 mitral prosthesis was introduced on the market in 1965 to reduce the high incidence of ball variance and thromboembolism of the previous model. We report the case of a Starr-Edwards Model 6120 which had been in place for 44 years and was still well functioning with no apparent structural damage.

Scanning Electron Microscopy of Aortic Medial Changes in Aortic Ascending Dilatation

The study of cystic cavities and collagen fibers fragmentation is useful to for a better knowledge of pathogenesis and surgical therapy of medial ascending aortic degeneration. Thus, the aim of this study was to describe by scanning electron microscopy the surfaces and shape of the cysts, measure their area, and identify microcystic spaces related to this degenerative disease. Scanning electron microscopy analysis was performed in 16 out of 36 patients who underwent surgery for ascending aorta dilatation with associated aortic valve disease. The aortic medial wall showed a cribrose appearance at low magnification (×50–100) and the intima was effuse. At high magnification (×500–2000), small cavities (clefts) lined by normal or fragmented elastic fibers and large cavities (pseudocystes) with anfractuous borders lined by fragmented elastic fibers and smooth muscle cells were observed. Furthermore, in the outer media wall microvessels lined by endothelium were also observed. These changes were lacking or less pronounced in normal aorta. SEM allows one to better identify the pathological cavities and to differentiate them from microvessels. These pathological cavities are more numerous and larger in the convexity than in the concavity of the aorta in according to our previous morphological and morphometric findings in asymmetrical aorta dilatation.