Michele Mottola

Multiple composite grafts (k, π or double-Y) in coronary artery surgery: a choice or a necessity?

OBJECTIVES Composite grafts allow complete arterial revascularization with minimal aortic manipulations. The Y-T configuration supplies all distal branches adequately, whereas it is unclear whether complex composite configurations (K, Π or double-Y) are equally at rest or when challenged by maximal requirements. METHODS Forty-seven patients who underwent off-pump coronary artery revascularization by multiple arterial composite grafts (K, Π or double-Y) were retrospectively evaluated. Indication for this surgical option was porcelain aorta or conduit unavailability. Composite systems were evaluated by intraoperative flow measurements and perioperative transthoracic Doppler ultrasonography, 12 months later also by exercise test, sestamibi scintigraphy at rest and during induced hyperaemia and by 64-slice multidetector CT angiography. RESULTS A total of 141 distal anastomoses were implanted as composite grafts. Perioperative flow measurements and 12-month Doppler ultrasonography were adequate at rest. At stress test, chest pain and/or induced ECG evidence of ischaemia are found in 16 patients (39%). During dipyridamole-induced hyperaemia, single-photon emission computed tomography image revealed that mean summed stress score was 7.2 ± 5.7, summed difference score 5.3 ± 4.2 and coronary flow reserve 1.7 ± 0.2. CONCLUSIONS Multiple composite grafts, albeit adequate at rest, were unable to meet flow requirements during maximal hyperaemia. In daily practice, their use must be not a choice but rather a necessity in those patients without alternative options.

Y grafts with the left internal mammary artery and radial artery. Mid-term functional and angiographic results. Cohort study.

BACKGROUND This retrospective cohort study investigated the functional and haemodynamic mid-term results over 3-years follow up of the left internal mammary artery (LIMA) conduit in composite Y-graft configuration with radial artery (RA) in a population of patients who underwent off-pump coronary artery bypass grafting (CABG). METHODS 148 patients who underwent off-pump CABG with composite Y-graft, were evaluated over 3-year follow up. Two-day dipyridamole induced maximal hyperaemia/rest 99mTc-sestamibi was scheduled preoperatively and 36 months after surgery for functional evaluation. Morphological evaluation was performed by 64 slice multidetector computed tomography (CT) 36 months after surgery. RESULTS Clinical adverse events were rare within 3 years follow up. Minimal to severe scintigraphic evidence of stress induced ischaemia occurred in 24 patients. Left ventricular (LV) hypertrophy (HR 3.1; 95% CI, 1.5-9.3; p = 0.01) and poor coronary run off (HR 4.1; 95% CI, 2.1-10.8; p = 0.005) were significant multivariate predictors of reversible stress induced ischaemia. 64 slice multidetector CT showed that the main stem of Y composite grafts was patent in all patients, while distal LIMA or RA was stenosed or occluded in 9 patients. CONCLUSION Composite Y-graft was adequate to meet the flow requirements of target coronary artery either at rest or during maximal hyperaemia. The use of Y-graft should be carefully evaluated in patients with LV hypertrophy and/or poor coronary run-off.

Comparison of Left Ventricular Myocardial Structure and Function in Patients with Aortic Stenosis and Those with Pure Aortic Regurgitation

Objective: We aimed to support the structural and functional distinction between aortic stenosis (AS) and aortic regurgitation (AR). Methods: Biopsy specimens taken from 70 selected patients (35 with AS and 35 with AR) undergoing aortic valve replacement (AVR) were analyzed for their cardiomyocyte dimensions and structure, interstitial fibrosis and contractile function. To determine normal values of contractile function, 10 donor hearts were analyzed. Results: Cardiomyocyte diameter was higher in AS than in AR (22.7 ± 2.2 vs. 13.2 ± 0.7 µm, p < 0.001). Length was higher in AR (121.2 ± 9.4 vs. 95.6 ± 3.7 µm, p < 0.001). Collagen volume fraction was increased in both AS and AR, but was lower in the AS specimens (7.7 ± 2.3 vs. 8.9 ± 2.3, p = 0.01). Myofibril density was reduced in AR (38 ± 4 vs. 48 ± 5%, p < 0.001). Cardiomyocyte diameter and length were closely linked to the relative left ventricular (LV) wall thickness (R2 = 0.85, p < 0.001 and R2 = 0.68, p = 0.003). The cardiomyocytes of AS patients had higher Fpassive (6.6 ± 0.3 vs. 4.6 ± 0.2 kN/m2, p < 0.001), but their total force was comparable. Fpassive was also significantly higher in AS patients with restrictive rather than pseudo-normal LV filling (7.3 ± 0.5 vs. 6.7 ± 0.6, p = 0.004). In AS patients, but not in AR patients, Fpassive showed a significant association with the cardiomyocyte diameter (R2 = 0.88, p < 0.001 vs. R2 = 0.31, p = 0.6). Conclusions: LV myocardial structure and function differ in AS and AR, allowing for compensative adjustment of the diastolic/systolic properties of the myocardium.

Continuative statin therapy after percutaneous coronary intervention improves outcome in coronary bypass surgery: a propensity score analysis of 2501 patients.

OBJECTIVES A history of percutaneous coronary intervention increases the risk of death and complications of coronary artery bypass grafting. This retrospective multicenter study evaluated the impact of continuative use of statin on postoperative outcomes when subsequent elective coronary artery bypass grafting is required after percutaneous coronary intervention. METHODS Among 14,575 patients who underwent isolated first-time coronary artery bypass grafting between January 2000 and December 2010, 2501 who had previous percutaneous coronary intervention with stenting and fulfilled inclusion criteria were enrolled. Continuative statin therapy was used in 1528 patients and not used in 973 patients. Logistic multiple regression and propensity score analyses were used to assess the risk-adjusted impact of statin therapy on in-hospital mortality and major adverse cardiac events. The Cox proportional hazards model was constructed to assess the effect of continuative statin therapy on 24-month outcome. RESULTS At multivariate analysis, age more than 70 years, 3-vessel or 2-vessel plus left main coronary disease, multivessel percutaneous coronary intervention, ejection fraction 0.40 or less, diabetes mellitus, and logistic European System for Cardiac Operative Risk Evaluation 5 or greater were independent predictors of hospital mortality and major adverse cardiac events. After propensity score matching, conditional logistic regression analysis demonstrated that continuative statin therapy before coronary artery bypass grafting reduced the risk for hospital and 2-year mortality (odds ratio [OR], 0.27; 95% confidence interval [CI], 0.12-0. 57; P=.004 and OR, 0.6; 95% CI, 0.36-0.96; P=.04, respectively) and major adverse cardiac events (OR, 0.31; 95% CI, 0.18-0.78; P=.003 and OR, 0.5; 95% CI, 0.34-0.76; P=.006, respectively). CONCLUSIONS Long-term statin treatment after percutaneous coronary intervention improves early and midterm outcome when surgical revascularization will be required.

Treatment of a rapidly expanding thoracoabdominal aortic aneurysm after endovascular repair of descending thoracic aortic aneurysm in an old patient

BackgroundAortic pathology progression and/or procedure related complications following endovascular repair should always be considered mostly in older patients. We herein describe a hybrid procedure for treatment of rapidly expanding thoracoabdominal aneurysm following endovascular treatment of a descending thoracic aortic aneurysm in an older patient.Case presentationA 82-year-old man at 18 months after endovascular surgery for a contained rupture of descending thoracic aortic aneurysm revealed a type IV thoracoabdominal aneurysm with significant increase of the aortic diameters at superior mesenteric and renal artery levels. A hybrid approach consisting of preventive visceral vessel revascularization and endovascular repair of entire abdominal aorta was performed. Under general anaesthesia and by xyphopubic laparotomy, the infrarenal aneurysmatic aorta and common iliac arteries were replaced by a bifurcated woven prosthetic graf. From each of the prosthetic branches two reverse 14x7 mm bifurcated PTFE prosthetic grafts were anastomized to both renal arteries and to the celiac axis and superior mesenteric artery, respectively. Vessel ischemia was restricted to the time required for anastomosis. Three 10 cm Gore endovascular stent-grafts for a total length of 15 cm, were used. The overlapping of the stent-grafts was carried out from the bottom upwards, starting from the aorto-iliac prosthetic body up to the healthy segment of thoracic aorta, 40 mm from the previous stent-grafts.The patient was discharged on the 9th postoperative day.ConclusionThis technique offers the advantage of a less invasive treatment, reducing the risk of paraplegia, visceral ischaemia and pulmonary complications, mostly in older patients.

Left ventricular-assisted myocardial revascularization favorably affects levels of circulating adhesion molecules and lung function

BACKGROUND We investigated whether the use of left ventricular-assisted (LVA) technique in beating heart myocardial revascularization would exert less impact on patients adhesion molecules and oxygenation index as compared with conventional cardiopulmonary bypass (CPB). METHODS Sixty-six consecutive patients undergoing myocardial revascularization were randomly assigned either to LVA (group A, 34 patients) or CPB (group B, 32 patients). Adhesion molecules and oxygenation indexes were measured at baseline and at various time points postoperatively. RESULTS Pre-operative clinical and demographic data did not differ between the 2 groups. The 2 groups were also similar with respect to mortality, number of grafts performed, duration of extracorporeal circulation, and need for inotropes. However, postoperatively patients treated with LVA had a reduced levels of adhesion molecules compared with patients treated with CPB, as indicated by a significant difference in endothelial leukocyte adhesion molecule-1 (P = .002), intercellullar adhesion molecule-1 (P = .0001), and vascular cell adhesion molecule-1 (P = .004). The oxygenation index at 1 (P = .04) and 3 hours (P = .03) postoperatively was better in the LVA group than in the CPB group. CONCLUSION Patients undergoing beating heart myocardial revascularization with LVA show reduced levels of adhesion molecules and better oxygenation index than patients treated with CPB.

Severe prosthesis-patient mismatch after aortic valve replacement for aortic stenosis: Analysis of risk factors for early and long-term mortality

BACKGROUND Severe prosthesis-patient mismatch (PPM) is considered to further decrease survival compared to moderate PPM. This study aimed to assess the impact of severe PPM on survival after aortic valve replacement (AVR). METHODS We retrospectively studied 2404 consecutive patients with PPM who underwent first-time AVR for pure stenosis between January 2003 and December 2014. Mismatch was moderate for indexed effective valve orifice >0.65 to <0.85cm2/m2 and severe for indexed effective valve orifice ≤0.65cm2/m2. Moderate mismatch occurred in 2165 patients (89%), and severe in 239 (11%) patients. Logistic multiple regression with bootstrapping and propensity score analyses were performed using 29 clinical and demographic data to assess the risk-adjusted impact of severe mismatch on mortality. The Cox proportional hazards model was constructed to process the long-term outcome. RESULTS Early mortality was 2.3% (51/2165) in moderate mismatch group and 3.7% (9/239) in severe mismatch group (p=0.2). Mortality at 5 and 10 years, was 218/1470 (14.8%) and 252/585 (43.1%) for moderate mismatch and 43/198 (21.7%) and 61/105 (58.1%) for severe mismatch (p=0.02 and p=0.006). Multivariable predictors of late mortality were as follows: age ≥70 years, left ventricular ejection fraction ≤40%, indexed left ventricular mass >220g/m2 and concomitant coronary artery revascularization. After propensity score matching, conditional logistic regression analysis demonstrated no relationship between severe mismatch and increased mortality at 5 postoperative years (HR, 0.9; 95% CI, 0.7-1.6; p=0.06), whereas it was significant at 10 postoperative years (HR, 1.9; 95% CI, 1.2-2.5; p=0.03). During the follow-up, severe mismatch was associated with more frequent hospital readmissions for cardiac events (0.12 vs. 0.08 events/patient/year, p=0.007). CONCLUSIONS Patients with severe mismatch had lower long-term survival and higher incidence of hospital readmissions for cardiac events. However, the effect of severe mismatch on outcome appeared mainly related to the preoperative risk profile of each patient.