Maurizio Roberto

The anterior spinal artery: the main arterial supply of the human spinal cord--a preliminary anatomic study.

Paraplegia is the most feared complication of surgery of the thoracic aorta. Controversy continues regarding the continuity of the anterior spinal artery (ASA). We studied the arterial vascularization of human spinal cord to indagate ASA continuity and possible anatomic variations of the arteria radicularis magna (ARM). Methods. From July 1998 to January 1999, 31 spinal cords from adult cadavers of both sexes were studied (mean age 72 ± 12 years). The cause of death was well established in each case and no one had spinal, cerebral, or significant aortic disease. The abdomen, thoracic viscera, and vessels were removed after 24 to 36 hours from death; only the upper trunks of the aorta were left in situ. The anterior vertebral spinal column was exposed and the attached muscles were divided. The vertebral bodies were removed with an electrical oscillating saw. The spinal cord in situ was exposed after a longitudinal paramedian incision of the dura mater. In all cases the course of the ASA was visualized and the distribuFrom the Department of Cardiovascular Surgery, Centro Cardiologico “I Monzino” Foundation IRCCS,a and II Department of Pathology,b University of Milan, Milan, Italy. Received for publication April 6, 1999; accepted for publication Sept 20, 1999. Address for reprints: Maurizio Roberto, MD, Department of Cardiovascular Surgery, “I Monzino” Foundation IRCCS, via Parea 4, 20138 Milan, Italy. J Thorac Cardiovasc Surg 2000;119:376-9 Copyright

Long-term effectiveness of cardiac resynchronization therapy in heart failure patients with unfavorable cardiac veins anatomy comparison of surgical versus hemodynamic procedure.

OBJECTIVES This study sought to compare clinical, echocardiographic, and cardiopulmonary exercise testing response to cardiac resynchronization therapy (CRT) in patients with unfavorable anatomy of coronary sinus (CS) veins, randomized to transvenous versus surgical left ventricular (LV) lead implantation. BACKGROUND CRT efficacy depends on proper positioning of the LV lead over the posterolateral wall. A detailed pre-operative knowledge of CS anatomy might be of pivotal importance to accomplish a proper LV lead placement over this area. METHODS Study population included 40 patients (age 66 ± 4 years) with heart failure and indication to CRT, with unsuitable CS branches anatomy documented by pre-operative multislice computed cardiac tomography; 20 patients (Group 1) underwent surgical minithoracotomic LV lead implantation whereas 20 (Group 2) were implanted transvenously. New York Heart Association functional class, echocardiographic, and cardiopulmonary exercise testing data were assessed before and 1 year after CRT-system implant. RESULTS In all Group 1 patients, the LV leads were placed over the middle-basal segments of the posterolateral wall of the LV. This was not possible in Group 2 patients. One year after CRT, in Group 1, a significant improvement of New York Heart Association functional class, LV ejection fraction (from 28.8 ± 9.2% to 33.9 ± 7.2%, p < 0.01), LV end-systolic volume (from 165 ± 53 ml to 134 ± 48 ml, p < 0.001), and peak Vo(2)/kg (from 10.4 ± 4.5 ml/kg/min to 13.1 ± 3.1 ml/kg/min, p < 0.02) was observed. However, no improvement was observed in Group 2: LV ejection fraction varied from 27.4 ± 4.8% to 27.4 ± 5.7% (p = 0.9), LV end-systolic volume from 175 ± 46 ml to 166 ± 44 ml (p = 0.15), and peak Vo(2)/kg from 11.2 ± 3.2 ml/kg/min to 11.3 ± 3.4 ml/kg/min (p = 0.9). Changes after CRT between groups were highly significant. CONCLUSIONS In the setting of unfavorable CS branches of anatomy, CRT by a surgical minithoracotomic approach is preferable to transvenous lead implantation.

Oxygen metabolism during and after cardiac surgery: role of CPB

BACKGROUND Cardiopulmonary bypass (CPB) has been reported to increase oxygen metabolism and to influence the relation between oxygen consumption (VO(2)) and delivery (DO(2)) in the early hours after cardiac surgery. To investigate the role of CPB, we studied oxygen metabolism in coronary artery bypass procedures performed on-pump (CABG) and off-pump (OPCAB). METHODS Twenty-five patients were randomized to undergo CABG (n = 14) or OPCAB (n = 11). All patients received the same anesthetic management. Oxygen metabolism variables were assessed before induction of anesthesia and up to 18-hours after surgery. RESULTS At baseline, before induction of anesthesia, there were no differences between CABG and OPCAB in oxygen consumption (VO(2)), delivery (DO(2)), or extraction (ExO(2)). After surgery VO(2) and ExO(2) increased in both groups, while DO(2) decreased. No significant differences between CABG and OPCAB were detected in postoperative VO(2), DO(2), and ExO(2) levels. The relation between VO(2) and DO(2) was very similar in CABG and OPCAB patients throughout the study, and no significant differences were detected in slopes and intercepts of the regression lines between CABG and OPCAB at all time points. There was, however, a significant effect of time on the relation between VO(2) and DO(2): this relation was stronger in the postoperative period, and the slope of this relation increased over time as well. CONCLUSIONS A hypermetabolic state and progressive and significant increases in the strength of the relationship between VO(2) and DO(2) and in the slope of this relationship occur after both CABG and OPCAB. Cardiopulmonary bypass is not responsible for these changes in oxygen metabolism.

False hydatic aneurysm of the thoracic aorta

In this article we report the successful treatment of a lower descending thoracic aorta hydatidosis that mimicked a posterior saccular aneurysm; surgical excision was performed and the aorta was repaired with a prosthetic Dacron patch. At a 26-month follow-up, the patient is alive and conducting a normal life. Discussion about the management of this rare case also is given.

In-hospital mortality risk assessment in elective and non-elective cardiac surgery: a comparison between EuroSCORE II and age, creatinine, ejection fraction score

OBJECTIVES Age, creatinine, ejection fraction (ACEF) score is a simplified algorithm for prediction of mortality after elective cardiac surgery. Although mainly conceived for elective cardiac surgery, no information is available on its performance in non-elective surgery and on comparison with the new EuroSCORE II. This study was undertaken to compare the performance of ACEF score and EuroSCORE II within classes of urgency. METHODS Complete data on 13 871 consecutive patients who underwent major cardiac surgery in a 6-year period were retrieved from three prospective institutional databases. Discriminatory power was assessed using the c-index and h with Delong, bootstrap and Venkatraman methods. Calibration was evaluated with calibration curves and associated statistics. RESULTS The in-hospital mortality rate was 2.5%. The discriminatory power of ACEF score within elective and non-elective surgery was similar (area under the curve (AUC) 0.71, 95% confidence interval (CI) 0.67-0.74 and AUC 0.68, 95% CI 0.62-0.73, respectively) but significantly lower than that of EuroSCORE II (AUC 0.80, 95% CI 0.77-0.83 for elective surgery; AUC 0.82, 95% CI 0.78-0.85 for non-elective surgery). The calibration patterns were different in the two subgroups, but the summary statistics underscored a miscalibration in both of them (U-statistic and Spiegelhalter Z-test P-values <0.05). Even the calibration of EuroSCORE II was insufficient, although it was demonstrated to be well calibrated in the first tertile of predicted risk. CONCLUSIONS This study demonstrated that the performance of ACEF score in predicting in-hospital mortality in elective and non-elective cardiac surgery is comparable. Nonetheless, it is not as satisfactory as the new EuroSCORE II, as its discrimination is significantly lower and it is also miscalibrated.

Role of hyperbaric oxygen therapy in the treatment of postoperative organ/space sternal surgical site infections

BackgroundA prospective trial was designed to evaluate the effect of hyperbaric oxygen (HBO) therapy on organ/space sternal surgical site infections (SSIs) following cardiac surgery that requires sternotomy.MethodsA total of 32 patients who developed postoperative organ/space sternal SSI were enrolled in this study from 1999 through 2005. All patients were offered HBO therapy. Group 1 included the patients who accepted and were able to undergo HBO therapy (n = 14); group 2 included patients who refused HBO therapy or had contraindications to it (n = 18).ResultsThe two groups were well matched at baseline with comparable preoperative clinical characteristics and operative factors. Staphylococcus was the most common pathogen for both groups. The duration of infection was similar in groups 1 and 2 (31.8 7.6 vs. 29.3 5.7 days, respectively, p = 0.357). The infection relapse rate was significantly lower in group 1 (0% vs. 33.3%, p = 0.024). Moreover, the duration of intravenous antibiotic use (47.8 ± 7.4 vs. 67.6 ± 25.1 days, p = 0.036) and total hospital stay (52.6 ± 9.1 vs. 73.6 ± 24.5 days, p = 0.026) were both significantly shorter in group 1.ConclusionHyperbaric oxygen is a valuable addition to the armamentarium available to physicians for treating postoperative organ/space sternal SSI.

Quadricuspid aortic valve plasty: is it worth it to repair as an alternative to substitution?

We present the case of a 49-year-old man with an abnormal aortic valve formed by four cusps (three equal large cusps and one smaller cusp; type 1 according to Hurwits and Roberts classification) with a marked lack of coaptation that caused a severe aortic valve insufficiency. The patient underwent a repair of the defect with a tricuspidalization of the aortic valve, restoring the normal coaptation of the cusps and the normal function of the aortic valve. Postoperative course was unremarkable. The early follow-up showed a mild aortic valve insufficiency.

Acute effects of 17β-estradiol on left internal mammary graft after coronary artery bypass grafting

Abstract Background . Vasospasm of arterial conduits used for coronary surgical procedures is an important cause of postoperative graft failure. Mounting experimental evidence suggests that estrogen reverses acetylcholine-induced vasospasm of the coronary arteries in animals and humans. Estrogen also affects endothelium-derived constrictor factors. We therefore investigated the in vivo vasomotor responses to transdermal 17β-estradiol of the left internal mammary artery (LIMA) grafted on the anterior descending coronary artery. Methods . We studied 20 women, mean age of 62 ± 7.2 years (range, 48 to 73 years), who had undergone cardiopulmonary bypass for coronary artery bypass grafting. They received transdermal 17β-estradiol on the fifth day after operation. The diameter, cross-sectional area, and blood flow of the LIMA graft were measured by transthoracic color Doppler echography before (basal values) and after the transdermal administration of 50 μg of 17β-estradiol (control). Results . LIMA graft vasodilation after the administration of 17β-estradiol was observed. A significant increase in diameter (2.06 ± 0.4 mm versus 2.37 ± 0.28 mm; p = 0.035) and cross-sectional area (3.45 ± 1. 2 mm 2 versus 4.24 ± 1 mm 2 ; p = 0.039) was registered. The LIMA graft mean flow increased by 49% (44.76 ± 27.19 mL/min versus 56.62 ± 27.69 mL/min), but this increase was not statistically significant ( p = 0.06). Conclusions . The acute postoperative transdermal administration of 17β-estradiol induced a significant increase of LIMA graft diameter and cross-sectional area in postmenopausal women who underwent coronary artery bypass grafting. The LIMA graft vasodilation was also associated with an improvement in LIMA blood flow.

D-dimer is associated with arterial and venous coronary artery bypass graft occlusion

Objective In this observational prospective study, we assessed the role of clinical variables and circulating biomarkers in graft occlusion at 18 months to identify a signature for graft occlusion. Methods A total of 330 patients undergoing primary elective coronary artery bypass grafting were enrolled. Blood collection for biomarker assessment was performed before surgery and discharge. Patients were then scheduled to undergo coronary computed tomography angiography at 18 months follow‐up, and 179 patients underwent coronary computed tomography angiography 18 ± 2 months postoperatively. Results There were 46 of 503 (9.1%) occluded grafts; of these, 29 (63%) were venous and 17 (37%) were arterial grafts; overall, 43 of 179 patients (24%) had at least 1 occluded graft. Logistic mixed effects model assessing independent factors associated with graft occlusion identified that lower D‐dimer levels at baseline (odds ratio [OR], 2.58; 95% confidence interval [CI], 1.36‐4.89; P = .00) and total protein content at discharge (OR, 1.09; 95% CI, 1.01‐1.19; P = .028) were related to overall graft occlusion at follow‐up, along with an arterial graft other than the left internal thoracic artery (OR, 2.92; 95% CI, 1.24‐6.9; P = .078); moreover, a venous graft emerged was possibly associated with graft occlusion (OR, 1.51; 95% CI, 0.95‐2.39; P = .078). By separately analyzing saphenous vein and arterial grafts, D‐dimer levels (OR, 2.67; 95% CI, 1.15‐6.2; P = .022 and OR, 2.5; 95% CI, 1.01‐7.0; P = .05 for venous and arterial graft, respectively) were still associated with arterial and venous graft occlusion at follow‐up. Conclusions We identified D‐dimer as a biomarker associated with arterial and venous grafts occlusion. This may help stratify patients at risk of graft failure and identify new molecular targets to prevent this complication.

Five-year echocardiographic follow-up after TAVI: structural and functional changes of a balloon-expandable prosthetic aortic valve

Aims Scarce data are available on the long-term structural and functional changes of prosthetic valves after transcatheter aortic valve implantation (TAVI). The objective was to evaluate with echocardiography the long-term structural and functional changes of prosthetic valves after TAVI. Methods and results Structural valve deterioration (SVD) was defined as leaflet thickening ≥3mm, presence of calcification and abnormal leaflet motion. Five-year echocardiographic follow-up was available in 96 out of 318 patients who underwent TAVI with a balloon-expandable device between April 2008 and December 2011. At 1-year follow-up, no patient showed SVD. At 5-year follow-up, SVD were observed in 29 (30%) patients who showed also a significant reduction of aortic valve area (AVA) together with an increase of mean and peak aortic pressure gradients at the latest echocardiography evaluation. Moreover, rate of central aortic valve regurgitation ≥2 was higher in SVD patients as compared to those without SVD, while there was no difference in terms of paravalvular regurgitation. Despite SVD, one patient only reached the criteria for severe stenosis and no reintervention was needed at 5-year follow-up. Variables independently associated with SVD were female sex, small body surface area, use of a 23 mm valve, and small AVA at pre-discharge echocardiogram. Conclusion At 5-year follow-up, 30% of patients who underwent TAVI with a balloon-expandable valve showed initial SVD. However, SVD was not associated with severe stenosis in most of the patients and had no significant impact on and clinical outcome.