Carlo Fino

The double-orifice technique as a standardized approach to treat mitral regurgitation due to severe myxomatous disease: surgical technique

OBJECTIVESnMitral-valve repair in Barlows disease is challenging; conventional techniques are difficult to perform, and there is a high risk of a postoperative suboptimal result. Double-orifice repair has been applied in a standardized approach to treat patients with severe mitral regurgitation and bileaflet prolapse due to Barlows disease.nnnMETHODSnSince 1993, 82 patients with severe mitral regurgitation due to Barlows disease underwent correction applying the edge-to-edge concept. They were submitted to double-orifice repair in a standardized fashion, suturing the middle portions of both leaflets.nnnRESULTSnThere were no hospital deaths. The repair was unsatisfactory in one patient who underwent valve replacement soon after the repair. The mean postoperative valve area was 3.7+/-0.79 cm(2) against a mean preoperative value of 9.2+/-2.1 cm(2). No or mild regurgitation was found in all but three patients who showed moderate residual regurgitation. There were no late deaths. Freedom from reoperation was 86+/-14% at 5 years. At the latest follow-up, all patient but one were New York Heart Association (NYHA) functional class I, and echo-Doppler assessment of valve reconstruction showed stable valve function in all patients.nnnCONCLUSIONSnThe double-orifice repair can be used as a standardized approach to treat valve regurgitation due to Barlow disease with low risk and good early and mid-term results.

Warm-blood cardioplegia with low or high magnesium for coronary bypass surgery: a randomised controlled trial

OBJECTIVEnMagnesium (Mg²⁺) is cardioprotective and has been routinely used to supplement cardioplegic solutions during coronary artery bypass graft (CABG) surgery. However, there is no consensus about the Mg²⁺ concentration that should be used. The aim of this study was to compare the effects of intermittent antegrade warm-blood cardioplegia supplemented with either low- or high-concentration Mg²⁺.nnnMETHODSnThis study was a randomised controlled trial carried out in two cardiac surgery centres, Bristol, UK and Cuneo, Italy. Patients undergoing isolated CABG with cardiopulmonary bypass were eligible. Patients were randomised to receive warm-blood cardioplegia supplemented with 5 or 16 mmol l⁻¹ Mg². The primary outcome was postoperative atrial fibrillation. Secondary outcomes were serum biochemical markers (troponin I, Mg²⁺, potassium, lactate and creatinine) and time-to-plegia arrest. Intra-operative and postoperative clinical outcomes were also recorded.nnnRESULTSnData from two centres for 691 patients (342 low and 349 high Mg²⁺) were analysed. Baseline characteristics were similar for both groups. There was no significant difference in the frequency of postoperative atrial fibrillation in the high (32.8%) and low (32.0%) groups (risk ratio 1.03, 95% confidence interval, CI, 0.82-1.28). However, compared with the low group, troponin I release was 28% less (95% CI 55-94%, p=0.02) in the high-Mg²⁺ group. The 30-day mortality was 0.72% (n = 5); all deaths occurred in the high-Mg²⁺ group but there was no significant difference between the groups (p=0.06). Frequencies of other major complications were similar in the two groups.nnnCONCLUSIONSnWarm-blood cardioplegia supplemented with 16 mmol l⁻¹ Mg²⁺, compared with 5 mmol l⁻¹ Mg²⁺, does not reduce the frequency of postoperative atrial fibrillation in patients undergoing CABG but may reduce cardiac injury. (This trial was registered as ISRCTN95530505.).

High OPCAB Surgical Volume Improves Midterm Event-Free Survival

BACKGROUNDnThe aim of this study was to evaluate the midterm results of the initial phase of off-pump coronary artery bypass (OPCAB) surgery adoption in a single surgical unit, assessing the impact of procedural volume.nnnMETHODSnStudy participants were 312 patients who underwent OPCAB during the period between August 2000 and January 2005 at S. Croce Hospital. Of these patients, 126 patients with an indication selected for comorbidities or 1-vessel disease underwent OPCAB performed by 4 low-volume surgeons, and 186 unselected patients underwent OPCAB performed by a single high-volume surgeon.nnnRESULTSnOPCAB performed by low-volume surgeons was associated with less complete revascularization and less arterial conduit use. Early result analysis showed a low rate of in-hospital or 30-day adverse events. The 5-year survival was 0.88 (0.02 SE). OPCAB performance by a high-volume surgeon and complete revascularization were shown have a protective effect for midterm major adverse cardiac events (respectively, hazard ratio = 0.28, 95% confidence interval 0.11-0.74 and hazard ratio = 0.33, 95% confidence interval 0.15-0.73).nnnCONCLUSIONnOur study on the initial phase of OPCAB adoption suggests a benefit on midterm outcome from surgery performed by a high-volume surgeon.

Exercise Hemodynamic and Functional Capacity After Mitral Valve Replacement in Patients With Ischemic Mitral Regurgitation: A Comparison of Mechanical Versus Biological Prostheses

Background: In patients with ischemic mitral regurgitation requiring mitral valve replacement (MVR), the choice of the prosthesis type is crucial. The exercise hemodynamic and functional capacity performance in patients with contemporary prostheses have never been investigated. To compare exercise hemodynamic and functional capacity between biological (MVRb) and mechanical (MVRm) prostheses. Methods and Results: We analyzed 86 consecutive patients with ischemic mitral regurgitation who underwent MVRb (n=41) or MVRm (n=45) and coronary artery bypass grafting. All patients underwent preoperative resting echocardiography and 6-minute walking test. At follow-up, exercise stress echocardiography was performed, and the 6-minute walking test was repeated. Resting and exercise indexed effective orifice areas of MVRm were larger when compared with MVRb (resting: 1.30±0.2 versus 1.19±0.3 cm2/m2; P=0.03; exercise: 1.57±0.2 versus 1.18±0.3 cm2/m2; P=0.0001). The MVRm had lower exercise systolic pulmonary arterial pressure at follow-up compared with MVRb (41±5 versus 59±7 mmu2009Hg; P=0.0001). Six-minute walking test distance was improved in the MVRm (pre-operative: 242±43, post-operative: 290±50 m; P=0.001), whereas it remained similar in the MVRb (pre-operative: 250±40, post-operative: 220±44 m; P=0.13). In multivariable analysis, type of prosthesis, exercise indexed effective orifice area, and systolic pulmonary arterial pressure were joint predictors of change in 6-minute walking test (ie, difference between baseline and follow-up). Conclusions: In patients with ischemic mitral regurgitation, bioprostheses are associated with worse hemodynamic performance and reduced functional capacity, when compared with MVRm. Randomized studies with longer follow-up including quality of life and survival data are required to confirm these results.

Unsuspected Aortic Dissection in Patient with Diagnosis of Prosthesis Aortic Valve Dysfunction

A 74-year-old woman was admitted to our hospital for acute pulmonary oedema. She had undergone aortic valve replacement with a Bicarbon 23A 16 years before because aortic stenosis caused by rheumatic valve disease and during the same operation she received a mitral valve repair (commissurotomy) for mitral valve stenosis. Until February 2008 her clinical condition was good. On February 2012 she was admitted in hospital for atrial flutter with high ventricular response. She was treated with amiodarone and than after 4 days she was discharge. Transthoracic echocardiography (TTE) was performed and showed a left ventricle with normal volume and diameter, with ipokinesia of the apex, EF 45%, a normal aortic prosthesis motion, and a native mitral valve with mild stenosis. On March 2012 she was admitted again in our hospital for acute pulmonary oedema, auscultation revealed normal prosthetic valve opening and closing clicks and a grade 2/6 ejection systolic murmur. TTE showed an intermittent aortic prosthesis dysfunction with mean (24 mm Hg) and peak (100 mm Hg) aortic gradients, they were higher than previous values recorded one month before. Multiplan transesophageal echocardiography (TEE) was, therefore, performed and confirmed TTE data. Severe aortic valve prosthesis regurgitation occurred intermittently and than a pannus or a thrombus was suspected do to a partial occlusion of the leaflets. A cardiac catheterisation (CC) and a cinefluoroscopy (CF) were performed. On CC the coronary artery was without stenosis and the prosthesis valve was good. CF allowed proper visualization of the disks showing normal systolic motion and the prosthesis aortic valve has a good motion of the bileaflet (Figure 1). While the diagnosis of an intermittent aortic prosthesis valve dysfunction was done, the patients were admitted to the operating theatre where she had an aortic and mitral valve replacement. Sternotomy was performed and extracorporeal circulation was started. An aortotomy was done and no pannus Unsuspected Aortic Dissection in Patient with Diagnosis of Prosthesis Aortic Valve Dysfunction