Mitral valve replacement after MitraClip therapy.

BACKGROUND: MitraClip therapy (MCT) is becoming more popular to treat mitral regurgitation (MR) in high-risk patients. It is, however, expanding to lower risk patients with the idea that mitral valve (MV) repair can be performed if surgery will be necessary. We report our surgical experience in patients who underwent MCT and subsequently required MV surgery. METHODS: From February 2012 to September 2014, three patients out of 34 who underwent MCT (8.8%) needed surgery because of lesions resulting in new MR. Two of them had functional and the third one degenerative MR. Two patients with functional MR underwent emergency surgery for MV lesions adding a new severe MR, the third one, with degenerative MR, had surgery 377 days after MCT. RESULTS: The MV showed a perforation of the anterior leaflet in one case and P2 completely torn in the second case. MitraClip opening was difficult and caused further injury to the leaflets. The third case developed a severe MV stenosis. All three patients underwent MV replacement with a tissue valve. The postoperative course was uneventful and, after a mean of 14 months, all patients are alive and in NYHA class I or II. CONCLUSIONS: The risk of urgent or elective surgery after MCT reduces the possibility of conservative surgery, as the possibility of valve reconstruction is less likely following the severe clip implantation-induced tissue damages.

Modified surgical sequence in aortic and mitral valve replacement with or without tricuspid valve repair or replacement.

A mitral prosthesis, when implanted, can distort the aortic annulus, forcing to downsize the aortic prosthesis. Changing the sequence of tying the sutures (the aortic prosthesis first, then the mitral prosthesis) allows to insert an aortic true-sized prosthesis. In case of associated tricuspid valve surgery, the aortic prosthesis protrudes over the anteroseptal commissure area. The sutures on the tricuspid annulus can be passed before the aortic prosthesis is secured in place.

Repair or prosthesis insertion in ischemic mitral regurgitation: Two faces of the same medal.

OBJECTIVE: The proper treatment of chronic ischemic mitral regurgitation (CIMR) is still under evaluation. The different role of mitral valve repair (MVr) or mitral valve prosthesis insertion (MVPI) is still not defined. METHODS: From May 2009 to December 2011 167 patients with ejection fraction (EF) ≤ 40% had MV surgery for CIMR, MVr in 135 (80.8%) and MVPI in 32 (19.2%). Indication to MVPI was a MV coaptation depth > 10 mm. EF was lower (26 ± 7 vs 32 ± 6, p = 0.0000) in MVPI, whereas MR grade (3.6 ± 0.8 vs 2.7 ± 0.9, p = 0.0000), left ventricle dimensions (end diastolic, LVEDD, 62 ± 7 vs 57 ± 6 mm, p = 0.0001; end systolic, LVESD, 49 ± 8 vs 44 ± 8 mm, p = 0.0018), systolic pulmonary artery pressure (51 ± 22 vs 41 ± 16 mm Hg, p = 0.0037) and NYHA Class (3.6 ± 0.5 vs 2.8 ± 0.6, p = 0.0000) were higher. RESULTS: In-hospital mortality was similar (3.1 vs 3.7%) as well as 3-year survival (86 ± 6 vs 88 ± 4) and survival in NYHA Class I/II (80 ± 5 vs 83 ± 4). One hundred thirty nine patients had an echocardiographic evaluation after a minimum of 4 months (13 ± 8). EF rose significantly in both groups (from 26 ± 7% to 30 ± 4%, p = 0.0122, and from 32 ± 6% to 35 ± 8%, p = 0.0018). LVESD reduced significantly in both groups (from 49 ± 8 to 43 ± 9 mm, p = 0.0109, and from 44 ± 8 to 41 ± 7 mm, p = 0.0033). MR grade was significantly lower in patients who had MVPI (0.1 ± 0.2 vs 0.3 ± 0.3, p = 0.0011). CONCLUSIONS: With appropriate indications, MVPI is a safe procedure which provides similar results to MVr with lower MR return, even if addressed to patients with worse preoperative parameters.

Functional tricuspid regurgitation and the right ventricle: What we do not know is more than we know.

The tricuspid valve (TV) lies in between the right atrium and the right ventricle (RV), consisting of annulus, leaflets, chords and papillary muscles. The RV appears triangular-shaped in a lateral view and crescent-shaped in a cross-section one. In normal conditions, the septum is concave toward the left ventricle (LV) in both systole and diastole and the RV volume is larger than the LV volume, although its mass is a third of the LV. The strict relationship between the TV apparatus and the RV underlies the physiological mechanism of TV functioning, and so, the RV plays an important role in case of functional tricuspid regurgitation. Nevertheless, the systematic assessment of RV is still not performed mainly due to lack of standardization. Hence, new echocardiographic guidelines have recently been proposed to standardize the RV assessment using transthoracic 2D­echocardiography. 3D-echocardiography and MRI are more useful to measure volumes and ejection fraction; in particular, MRI is able to provide a tissue evaluation. Today, surgical strategies are directed mainly to the annulus with fluctuating results because functional tricuspid regurgitation is not due only to the annulus but also to the RV, which is difficult to assess, due to its evolution being unpredictable and complicated by the interaction with LV.

Posterior chordal cutting in rheumatic mitral regurgitation due to hypomobility of the posterior leaflet.

A technique is described for correction of mitral regurgitation when the posterior leaflet has a reasonable length (approximately 10 mm), but its movements are limited by thickened and short chords. To avoid further retraction when a band or a ring is positioned to force leaflets coaptation, native chords are replaced by artificial chords (leaving 10 mm of extra length), which are then cut. In 6 patients, after 6 months of follow-up, the results are good.

Resecting and nonresecting techniques for posterior mitral leaflet prolapse.

BACKGROUND: Posterior leaflet (PL) prolapse is commonly treated with quadrangular resection, but nonresecting techniques were proposed as an alternative. We evaluated our experience to identify specific indications to nonresecting techniques. METHODS: From March 2006 to February 2009, 60 patients were treated for PL prolapse, 21 using resecting (group R), and 39 nonresecting (group NR) techniques. Patients in group R had fibroelastic deficiency with isolated P2 prolapse and P1 or P3 (or both) thin or short (n = 15); need of excessive P2 resection (more than 1/3 of the posterior annulus) (n = 10); dominant or codominant circumflex artery (n = 10). Some of them were young and were operated on without preoperative coronary angiography (n = 4). RESULTS: One patient (1.7%) in group R died during the first 30 days after surgery. Three-year survival was 89.6 ± 4.5, similar in both groups. A postoperative echocardiogram was obtained 20 ± 6 months after surgery in every survivor. Mitral regurgitation decreased significantly soon after surgery without any significant modification at follow-up in both groups. CONCLUSIONS: nonresecting techniques provide good midterm results, similar to resecting ones. To resect or not resect part of the PL has, in our personal practice, its own indications and contraindications. Extensive use of artificial chords and reduction of PL height, when indicated, is able to provide other tools to safely expand mitral repair for PL prolapse.

Decision making after aspirin, clopidogrel and GPIIb/IIIa inhibitor use.

The expanding use of antiplatelet agents in patients who undergo coronary bypass grafting raises the problem of balancing the benefit of this treatment and the risk of increased bleeding after surgery. Aspirin and clopidogrel have different mechanisms of actions, but have in common the irreversibility of the inhibition mechanism. Even if platelets half-life is around 10 days, it is not necessary to wait for this period of time. It can be reasonable to discontinue aspirin two to three days and clopidogrel five days before surgery, even if it was recently suggested to reduce the discontinuation interval to two to three days for the clopidogrel as well. GPIIb/IIIa inhibitors have a short acting action. Reasonably, abciximab has to be stopped, when possible, at least 12 hours before surgery, preferably before 24 hours. On the contrary, tirofiban can also be stopped at the moment of skin incision without harmful effects. Very little is known of eptifibatide, but it seems that it is safe to stop it two to four hours before surgery. Patients with acute coronary syndrome do not need to discontinue any antiplatelet treatment.

A single-size band, 50 mm long, for tricuspid annuloplasty.

A technique for tricuspid annuloplasty is presented, using a flexible 50mm long band, where the annular circumference is reduced to a fixed value of 78.5mm (circumference of #25 mm sizer). From June to February 2007, 15 consecutive patients with tricuspid regurgitation (TR) underwent tricuspid repair using this technique. The first suture is passed at the level of the anteroseptal commissure, the last one in the zone of the septal annulus, 28.5mm from the first one. The remaining sutures are passed as usual. All the sutures are then adapted to a 50mm long band. After a mean of 5.4 months from surgery, all patients are alive and asymptomatic. One patient showed residual 2/4 TR, due to enlarged RV with high pulmonary pressure despite a well functioning mitral prosthesis. Mean gradient across the tricuspid valve was 2.5+/-0.4 mmHg. This technique for tricuspid repair is simple and reliable, providing effective and reproducible results.

Mitral valve repair for degenerative mitral regurgitation.

Mitral valve repair for degenerative mitral regurgitation is nowadays one of the most common valvular procedures. Different technical modifications were added to the original Carpentier's method, trying to maximise the stability of the results and to reduce the incidence of immediate complications and of late failure of the correction. Survival is good, even if recent reports showed that recurrence of mitral regurgitation can be higher than expected. Prolapse of the anterior leaflet remains challenging and is related to higher reintervention rates. Nevertheless, the overall success rate is high, and the increasing experience of the different surgical teams approaching this procedure will help maintain satisfactory and stable long-term results.

Longitudinal plication of the posterior leaflet in myxomatous disease of the mitral valve.

In selected cases, resection of a prolapsing scallop of the posterior leaflet (generally P2) is not advisable because of the excessive length of insertion of the scallop. In such cases, insertion of artificial chordae is advisable, but the height of the scallop needs to be reduced. We used longitudinal plication of the scallop(s) in which the height was excessive with "U" sutures in 11 consecutive patients. Early and intermediate echocardiographic results were fully satisfying, and we expect that the morphologic aspect of the repaired mitral valve will remain stable after a longer follow-up.

Single versus bilateral internal mammary artery for isolated first myocardial revascularization in multivessel disease: long-term clinical results in medically treated diabetic patients.

BACKGROUND: We evaluated our experience to investigate if the use of bilateral internal mammary artery (BIMA) grafting, with or without complementary saphenous vein grafts (SVG), increases the quality of the results of coronary bypass grafting in medically treated diabetic patients who undergo first myocardial revascularization, when compared with the use of a single left internal mammary artery (LIMA) and SVG. METHODS: From October 1991 to December 2001, 558 diabetic patients with multivessel coronary disease had first isolated myocardial revascularization using LIMA and SVG (group LIMA) in 217 cases and BIMA +/- SVG (group BIMA) in 341. Propensity score analysis identified 400 patients, 200 for each group, with similar preoperative characteristics. Thirty-day outcome and 8-year freedom from death from any cause, cardiac death, acute myocardial infarction (AMI), AMI in a grafted area, redo/percutaneous transluminal coronary angioplasty (PTCA), redo/PTCA in a grafted area, target cardiac events, and any event were evaluated. Follow-up ranged from 2.0 to 12.2 years (mean 6.0 +/- 2.0). RESULTS: There was no difference between groups except the cardiac deaths, which were significantly higher in the LIMA group (7 versus 0, p = 0.015). The BIMA group showed better 8-year freedom from death any cause (86.7 +/- 3.2 versus 79.5 +/- 4.1, p = 0.0274), cardiac death (96.3 +/- 1.4 versus 88.4 +/- 4.0, p = 0.0406), acute myocardial infarction (99.5 +/- 0.5 versus 92.0 +/- 3.9, p = 0.0092), and acute myocardial infarction in a grafted area (99.5 +/- 0.5 versus 93.4 +/- 3.7, p = 0.0204). Cox analysis confirmed that the use of LIMA and SVG was an independent predictor for lower freedom from death (hazard ratio [HR] = 1.8, p = 0.0310), cardiac death (HR = 1.9, p = 0.0426), AMI (HR = 9.7, p = 0.0033) and AMI in a grafted area (HR = 8.2, p = 0.0410). CONCLUSIONS: In diabetic patients with multivessel disease who undergo first myocardial revascularization, BIMA +/- SVG provides higher freedom from death, any cause, and cardiac-related death, if compared with LIMA + SVG. It plays a protective role in reducing the incidence of late AMI.

Septal reshaping

Left ventricular (LV) aneurysm is a complication of an acute myocardial infarction (AMI). Herein a new technique is described that is indicated when the postinfarctual scar involves the septum more than the free wall. The incision starts at the apex and is directed, parallel to LAD, toward the base of the heart. The septum is rebuilt using 1 or 2 U-stitches, passed from inside, to join the anterior wall to the septum. The starting point begins as high as the scar, maintaining an oblique direction toward the new apex. An oval dacron patch is then sutured from the septum (end of the direct suture through the border with the inferior septum) to the anterior wall (between the healthy and the scarred wall) up to the new apex. Thirty-day mortality is low. This procedure provides good midterm results. New York Heart Association class improved from 2.7±0.9 to 1.6±0.5 (P≪0.001). Left ventricle (end-diastolic and end-systolic) volume, reduced significantly. Stroke volume normalized and ejection fraction increased even if not significantly. Mitral regurgitation reduced significantly from 2.5 to 0.6. No new mitral regurgitation developed.

Late results of first myocardial revascularization in multiple vessel disease: single versus bilateral internal mammary artery with or without saphenous vein grafts.

OBJECTIVE(S): We evaluated our experience to investigate if the use of bilateral internal mammary artery (BIMA) grafting, with or without complementary saphenous vein grafts (SVGs), if compared to the use of single IMA and SVG(s), increases the quality of the results of coronary bypass grafting in patients younger than 75 years who undergo first myocardial revascularization. METHODS: From September 1986 to December 1999, 1602 patients younger than 75 years underwent first myocardial revascularization using left internal mammary (LIMA) to left anterior descending (LAD) and SVG(s) (n=576) or BIMA (one IMA on the LAD) with or without SVG(s) (n=1026). Propensity score analysis was used to select 1140 patients with the same preoperative and operative characteristics. Thirty day outcome was evaluated as well as 10-year freedom from death by any cause, cardiac death, acute myocardial infarction (AMI), AMI in a grafted area (GA), redo/PTCA, redo/PTCA in a GA, target cardiac events (death from cardiac cause, AMI in a GA, redo/PTCA in a GA), and any event. Follow-up ranged from 3.5 to 16.8 years (mean 7.3+/-4.8 years). RESULTS: Thirty day mortality was 2.8% in Group LIMA and 2.1% in Group BIMA, P n.s.; incidence of major complications was, respectively, 7.0 versus 5.4%, P n.s. Group BIMA showed better 10-year freedom from cardiac death (96.5+/-0.8 versus 91.3+/-1.4, P=0.0288), AMI (98.0+/-0.6 versus 94.3+/-1.2, P=0.0180), AMI in a GA (98.4+/-0.6 versus 94.7+/-1.1, P=0.0057) and target cardiac events (93.9+/-1.1 versus 86.3+/-1.8, P=0.0388). Cox analysis confirmed that LIMA+SV(s) was an independent risk factor from lower freedom from cardiac death, AMI, AMI in a GA and cardiac events. CONCLUSIONS: As freedom from cardiac events is a main target of any revascularization procedure, we think that, when a patient undergoes a first coronary surgery and is younger than 75 years, BIMA grafting should not be denied, especially if his life expectancy is higher than 10 years.

Partial clamping of the brachiocephalic trunk for total ascending aorta replacement without circulatory arrest: early and midterm results.

BACKGROUND: The aim of this study was to evaluate in elective patients the early and midterm results of partial clamping of the brachiocephalic trunk (BCT) for total ascending aorta replacement (TAAR) without circulatory arrest. Contraindications to the procedure were BCT/aortic arch calcifications and chronic aortic dissection. METHODS: The right radial artery was cannulated to monitor the systemic pressure after the BCT was partially clamped. A specially designed clamp was applied obliquely to occlude approximately 50% of the BCT and part of the aortic arch. The distal tip of the clamp was positioned in front of the left subclavian artery. From January 2002 to October 2003, 92 patients underwent TAAR. In 62 patients (67.4%), partial clamping of the BCT was used. Twenty of these patients underwent isolated TAAR, 27 underwent aortic valve replacement and TAAR, 11 had a Bentall operation, and 2 had a Cabrol operation. The aortic valve was spared in the remaining 2 patients. The mean (+/- SD) aortic cross-clamping and cardiopulmonary bypass times were 96 +/- 31 minutes and 116 +/- 43 minutes, respectively. RESULTS: Early mortality was 1.6% (1 patient). No cerebrovascular accidents occurred, demonstrating the safety of the technique. The major complications were acute respiratory insufficiency in 2 cases and acute renal failure in 5. The mean follow-up time was 9.0 +/- 6.5 months. The mean 18- month and event-free survival rate was 96.6% +/- 0.9%. CONCLUSION: Partial clamping of the BCT for TAAR without circulatory arrest provides good early and midterm clinical results. Aortic arch clamping is not associated with cerebrovascular accidents.

Myocardial revascularization with and without cardiopulmonary bypass: advantages, disadvantages and similarities.

OBJECTIVES: Off-pump coronary artery bypass surgery is becoming increasingly popular although its effectiveness remains controversial. Our goal was to investigate the effectiveness of on-pump and off-pump coronary artery bypass surgery on early (30 days) and long-term (5 years) clinical outcome in two groups of patients selected using propensity scores. METHODS: From November 1994 to December 2001, 4381 patients underwent isolated coronary surgery. Applying propensity score matching, 1922 patients were selected (off-pump n=961, on-pump n=961). RESULTS: Stepwise logistic regression analysis showed that the use of cardiopulmonary bypass was an independent predictor for early death, cerebral vascular accident, early negative primary endpoints (ENPEP), and early major events (EME). Five years freedom from both events was similar in the two groups. However, freedom from acute myocardial infarction (AMI) in grafted areas was higher in the off-pump than in the on-pump patients, a possible explanation being the lower postoperative creatine kinase myocardial band (CKMB) release. Grouping all patients according to CKMB peak release also showed that patients with normal release values had higher freedom from all cardiac events investigated. A subgroup analysis of 59 patients converted from off-pump to on-pump showed higher early mortality, ENPEP, and EME. Conversion, however, did not affect late clinical outcome. CONCLUSIONS: These results suggest that off-pump surgery reduces early mortality and morbidity. Conversion to on-pump carries high in-hospital mortality and morbidity. Long-term clinical outcome is similar in the two groups; however, off-pump patients seemed to have a higher freedom from AMI in the grafted area which might be related to the lower CKMB peak release when compared with patients undergoing on-pump surgery.

Immediate flow reserve of Y thoracic artery grafts: an intraoperative flowmetric study.

OBJECTIVES: Use of both internal thoracic arteries in a Y graft configuration can raise concerns about the possibility of the single left internal thoracic artery being able to meet the flow requirements of two or three distal territories. We evaluated intraoperatively the flow reserve of a Y thoracic artery graft distally anastomosed to the anterior and lateral territories. METHODS: In 21 patients who had Y thoracic artery grafts, the flow was measured in the main stem of the left internal thoracic artery, in the left internal thoracic artery branch, and in the right internal thoracic artery. A transit time Doppler flowmeter was used. Measurements were repeated after the injection of a bolus of 20 mug/kg dobutamine. RESULTS: At baseline condition, the mean blood flow was 44.8 +/- 24.2, 23.4 +/- 11.5, and 21.4 +/- 15.3 mL/min in the main stem of the left internal thoracic artery, in the left internal thoracic artery branch, and in the right internal thoracic artery, respectively. After dobutamine injection, these values increased to 93.2 +/- 49.8, 46.1 +/- 22.6, and 42.5 +/- 31.2 mL/min, respectively. Flow reserve was 2.1 +/- 0.6, 2.2 +/- 0.9, and 2.1 +/- 0.9 mL/min, respectively. CONCLUSIONS: Intraoperative injection of dobutamine increases the flow in the Y thoracic graft by more than two times, not only in the main stem but also in each branch. This finding attests to the safety of Y thoracic conduits in terms of hemodynamic potential.

Myocardial revascularization with and without cardiopulmonary bypass in multivessel disease: impact of strategy on midterm outcome.

BACKGROUND: In a previous study, we demonstrated that patients with multivessel disease benefit during the first postoperative month from elimination of cardiopulmonary bypass (CPB). We evaluated the midterm results of the same patients excluding the first postoperative month from the analysis. METHODS: From May 1997 to November 2000, 1,802 patients with multivessel disease survived the first postoperative month; 906 were operated on without (group A) and 896 with (group B) CPB. Follow-up ranged from 23 to 65 months (mean, 42 +/- 12 months). Four-year actuarial freedom from the following events was evaluated: death from any cause; cardiac death; acute myocardial infarction (AMI) in any territory; AMI in a grafted area; redo percutaneous transluminal coronary angioplasty (PTCA); redo PTCA in a target vessel; cardiac events (death from a cardiac cause, acute myocardial infarction on grafted vessel, redo PTCA on target vessel); and any event. RESULTS: No statistical difference was found between groups A and B with regard to freedom from any death (95.3 +/- 0.8 vs 95.7 +/- 0.7, p = 0.5160); from cardiac death (97.3 +/- 0.6 vs 97.5 +/- 0.6, p = 0.5345); from AMI (98.4 +/- 0.4 vs 98.7 +/- 0.4, p = 0.4655); from AMI in a grafted area (98.9 +/- 0.4 vs 98.7 +/- 0.4, p = 0.9374); from redo PTCA (97.9 +/- 0.5 vs 97.7 +/- 0.6, p = 0.8485); from redo PTCA in a grafted area (98.7 +/- 0.4 vs 98.5 +/- 0.5, p = 0.8774); from target cardiac events (95.8 +/- 0.7 vs 95.9 +/- 0.8, p = 0.6070); and from any event (92.9 +/- 0.9 vs 93.4 +/- 1.0, p = 0.3721). CONCLUSIONS: After exclusion of the first postoperative month, myocardial revascularization without CPB has midterm results similar to myocardial revascularization with CPB. In particular, failure of revascularization does not depend on intraoperative strategy.