Totally Endoscopic Replacement of the Ascending Aorta and the Aortic Root including the Aortic Valve via Right Mini-Thoracotomy: A Multicenter Study

Background: Recently, minimally invasive access via right anterolateral mini-thoracotomy (RAMT) has been gaining popularity in cardiac surgery. This approach is also an option for surgeons performing aortic surgery. The aim of this study is to present our surgical method, highlighting the total endoscopic minimally invasive approach via RAMT for replacement of the ascending aorta (AAR) with or without involvement of the aortic root and the aortic valve. Methods: Clinical data of 44 patients from three participating institutions with AAR with or without involvement of the aortic valve or aortic root via RAMT between April 2017 and February 2024 were retrospectively analyzed. According to surgical procedure, patients were divided into two groups, in the AAR and in the Wheat/Bentall group with concomitant valve or root replacement. Operative time, length of ventilation, perioperative outcome, length of intensive care unit (ICU) as well as postoperative hospital stay, and mid- and long-term results were retrospectively analyzed. Results: Mean age was 61.4 ± 10.7 years old with a frequency of male gender of 63.6%. Mean cardiopulmonary bypass (CBP) time and aortic cross-clamping time was 94.9 ± 32.5 min and 63.8 ± 25.9 min, respectively. CPB and aortic clamp time were significantly lower in AAR group. In the first 24 h, the mean drainage volume was 790.3 ± 423.6 mL. Re-thoracotomy due to bleeding was zero. Sternotomy was able to be avoided in all patients. Patients stayed 35.9 ± 23.5 h at ICU and were discharged 7.8 ± 3.0 days following surgery from hospital. Mean ventilation time was 5.8 ± 7.6 h. All patients survived and 30-day mortality was 0.0%. At a median follow-up time of 18.2 months, all patients were alive. The results were similar in both groups. Conclusions: The full endoscopic RAMT approach with 3D visualization is a safe, feasible and promising technique that can be transferred in the field of aortic surgery without compromising surgical quality, postoperative outcomes, or patient safety when performed by an experienced team in a high-volume center.

Mitral valve diseases: Pathophysiology and interventions

Valvular heart disease is common and increasingly prevalent among the elderly. The end result of valvular pathologies is cardiac failure and can lead to sudden death; thus, diagnosis and interventions are very important in the early stages of these diseases. The usual treatment methods of mitral regurgitation include percutaneous mitral valve repair, mitral valve replacement and minimally invasive surgery, whereas the treatment methods of mitral stenosis include percutaneous transluminal mitral commissurotomy and mitral commissurotomy as well as open surgical repair. Nonetheless, ongoing clinical trials are a clear indicator that the management of valve diseases is ever evolving. The focus of this paper is on the various pathologies of the mitral valve, their etiology and clinical management, offering a comprehensive view of mitral valve diseases.

Selective right middle and lower lobar blockade for minimally invasive cardiac surgery: a prospective, single-center, randomized controlled study

Background

Minimally invasive cardiac surgery (MICS) is increasingly performed due to faster recovery time and lower postoperative complications when compared with the traditional open surgery. However, hypoxemia in lung isolation duration after cardiopulmonary bypass (CPB) surgery has been the focus of anesthesiologists' attention. In the present study, we designed a novel lung isolation strategy to improve oxygenation using a bronchial blocker (BB) to isolate the right middle and lower lobes and preserve the ventilated right upper lobe without affecting the surgical field.

Methods

Patients who had undergone right lateral mini-thoracotomy, a MICS, between August 2018 and February 2019, were enrolled in this randomized controlled study. Patients were randomly divided into a modified lung isolation group (group M) and a conventional lung isolation group (group C). In group M, BBs were used to block the bronchus intermedius, while left-sided double lumen endotracheal tubes were used in group C to isolate the right lung. The primary outcome was to determine the number of patients who required an increase in ventilation volume due to hypoxemia during lung isolation after CPB.

Results

Sixty-one patients (30 in group C and 31 in group M) were enrolled. Five patients in group M were converted to right lung isolation due to poor surgical field exposure. During lung isolation after CPB, the number of patients with hypoxemia was lower in group M than group C (5/31 vs. 15/30, P=0.005).

Conclusions

The novel modified lung isolation strategy reduced the incidence of hypoxemia after CPB.

The analysis of left ventricular ejection fraction after minimally invasive surgery for primary mitral valve regurgitation

BACKGROUND

Although minimally invasive mitral valve surgery (MIMVS) has become the first choice for primary mitral regurgitation (MR) in recent years, clinical evidence in this field is yet limited. The main focus of this study was the analysis of preoperative (Pre), postoperative (Post), and 1-year follow-up (Fu) data in our series of MIMVS to identify factors that have an impact on the left ventricular ejection fraction (LVEF) evolution after MIMVS.

METHODS

We reviewed the perioperative and 1-year follow-up data from 436 patients with primary MR (338 isolated MIMVS und 98 MIMVS combined with tricuspid valve repair) to analyze patients' baseline characteristics, the change of LV size, the postoperative evolution of LVEF and its factors, and the clinical outcomes.

RESULTS

The overall mean value of ejection fraction (EF) slightly decreased at 1-year follow-up (mean change of LVEF: -2.63 ± 9.00%). A significant correlation was observed for preoperative EF (PreEF) und EF evolution, the higher PreEF the more pronounced decreased EF evolution (in all 436 patients; r = -.54, p < .001, in isolated MIMVS; r = -.54, p < .001, in combined MIMVS; r = -.53, p < .001). Statistically significant differences for negative EF evolution were evident in patients with mild or greater tricuspid valve regurgitation (TR) (in all patients; p < .05, odds ratio [OR] = 1.64, in isolated MIMVS; p < .01, OR = 1.93, respectively). Overall clinical outcome in New York Heart Association classification at 1 year was remarkably improved.

CONCLUSIONS

Our results suggest an excellent clinical outcome at 1 year, although mean LVEF slightly declined over time. TR could be a predictor of worsened follow-up LVEF in patients undergoing MIMVS.

Stepwise mitral valve repair for Barlow's disease via a minimally invasive approach

BACKGROUND AND AIM

Mitral regurgitation (MR) in Barlow's disease is complicated because of its mixed pathophysiology, leaflet billowing with or without organic prolapse, and abnormal annular dynamics that cause functional prolapse. Complex repair techniques, including aggressive leaflet resection and implantation of multiple artificial chordae, are conventionally performed; nevertheless, these are technically demanding, especially when performed using a minimally invasive approach. We aimed to standardize the repair technique for Barlow's disease and developed stepwise repair techniques.

METHODS

Of 292 patients who underwent isolated minimally invasive mitral valve repair for MR, 29 patients (seven females, age 49 ± 10 years) were found to have Barlow's disease. Our repair technique consists of the following three steps: (a) stabilization of the mitral annulus by placing annuloplasty ring sutures; (b) distinction between organic and functional prolapse by a saline injection test; and (c) targeted repair for organic prolapse by leaflet resection or chordal replacement.

RESULTS

Surgical techniques included leaflet resection in 22 patients, chordal replacement in 19 patients, and ring annuloplasty only in one patient. These procedures were applied to the anterior leaflet in one, posterior leaflet in eight, and both leaflets in 19 patients. The median annuloplasty ring size was 34 mm. The repair success rate was 100%. No patients developed moderate or greater MR during a mean follow-up period of 36 ± 21 months.

CONCLUSIONS

A stepwise repair strategy facilitates mitral valve repair in patients with Barlow's disease and provides excellent outcomes even via a minimally invasive approach.

Which Patients Are Candidates for Minimally Invasive Mitral Valve Surgery? - Establishment of Risk Calculators Using National Clinical Database

BACKGROUND

Although minimally invasive mitral valve surgery via a right minithoracotomy (MICS-mitral) is widely performed, no tool to evaluate its risk has been reported. We sought to establish MICS-mitral risk calculators using a national clinical database for selection of appropriate patients.Methods and Results:Between 2008 and 2015, 3,240 patients (mean age 59±14 years, males 1,950) underwent a MICS-mitral procedure in Japan and were registered in a national clinical database. We examined mortality and composite outcome (operative mortality, stroke, reoperation for bleeding) using multivariate analysis, then developed a risk calculator for each using stepwise analysis. Operative mortality was 1.1% and the composite outcome rate was 5%. In multivariate analysis, risk factors for operative mortality were shown to be age, respiratory dysfunction, thoracic aortic disease, myocardial infarction, body mass index >30, NYHA class IV, moderate or severe aortic regurgitation, mitral valve replacement, multiple valve surgery, and annual cases <10. ROC curve analysis of our prediction formulas for mortality and composite outcome revealed an area under the curve for operative mortality of 0.877 (95% confidence interval: 0.82-0.94, P<0.01) and for composite outcome of 0.665 (95% confidence interval: 0.62-0.71, P<0.01).

CONCLUSIONS

We developed risk calculator formulas using risk factors associated with both operative mortality and composite outcome. The present risk calculator formula is useful for patient selection and may influence future applications for this procedure.

Cell salvage processing of residual cardiopulmonary bypass volume in minimally invasive cardiac surgery

Several reports demonstrated positive effects of processing residual cardiopulmonary bypass volume using a cell salvage device in conventional open heart surgery via sternotomy on hemostasis. The present study aimed to investigate whether cell salvage processing has the same effects on postoperative blood loss and transfusion in minimally invasive cardiac surgery. Between July 2015 and April 2018, 80 consecutive patients undergoing minimally invasive aortic valve replacement via right anterolateral minithoracotomy were enrolled in the present study. Perioperative outcomes and coagulation data of 40 patients who were retransfused with processed cardiopulmonary bypass volumes were compared with those of 40 patients receiving unprocessed residual blood (control group). Postoperative blood loss in patients receiving processed residual blood was significantly less than that in the control group at 6 h (115 ± 50 vs. 73 ± 33 ml, p < 0.001) and 12 h (167 ± 70 vs. 125 ± 67 ml, p = 0.009) after surgery, and the rate of fresh frozen plasma use after surgery was significantly reduced in patients receiving processed residual blood (18 vs. 0%, p = 0.012). In conclusion, processing of residual cardiopulmonary bypass volume reduced postoperative blood loss and postoperative use of fresh frozen plasma and could be useful for hemostasis in minimally invasive cardiac surgery.

Possible mechanism of late systolic mitral valve prolapse: systolic superior shift of leaflets secondary to annular dilatation that causes papillary muscle traction

Progressive superior shift of the mitral valve (MV) during systole is associated with abnormal papillary muscle (PM) superior shift in late systolic MV prolapse (MVP). The causal relation of these superior shifts remains unclarified. We hypothesized that the MV superior shift is related to augmented MV superiorly pushing force by systolic left ventricular pressure due to MV annular dilatation, which can be corrected by surgical MV plasty, leading to postoperative disappearance of these superior shifts. In 35 controls, 28 patients with holosystolic MVP, and 28 patients with late systolic MVP, the MV coaptation depth from the MV annulus was measured at early and late systole by two-dimensional echocardiography. The PM tip superior shift was monitored by echocardiographic speckle tracking. MV superiorly pushing force was obtained as MV annular area × (systolic blood pressure - 10). Measurements were repeated after MV plasty in 14 patients with late systolic MVP. Compared with controls and patients with holosystolic MVP, MV and PM superior shifts and MV superiorly pushing force were greater in patients with late systolic MVP [1.3 (0.5) vs. 0.9 (0.6) vs. 3.9 (1.0) mm/m², 1.3 (0.5) vs. 1.2 (1.0) vs. 3.3 (1.3) mm/m², and 487 (90) vs. 606 (167) vs. 742 (177) mmHg·cm²·m^-2, respectively, means (SD), P < 0.001]. MV superior shift was correlated with PM superior shift ( P < 0.001), which was further related to augmented MV superiorly pushing force ( P < 0.001). MV and PM superior shift disappeared after surgical MV plasty for late systolic MVP. These data suggest that MV annulus dilatation augmenting MV superiorly pushing force may promote secondary superior shift of the MV (equal to late systolic MVP) that causes subvalvular PM traction in patients with late systolic MVP. NEW & NOTEWORTHY Late systolic mitral valve prolapse (MVP) is associated with mitral valve (MV) and papillary muscle (PM) abnormal superior shifts during systole, but the causal relation remains unclarified. MV and PM superior shifts were correlated with augmented MV superiorly pushing force by annular dilatation and disappeared after surgical MV plasty with annulus size and MV superiorly pushing force reduction. This suggests that MV annulus dilatation may promote secondary superior shifts of the MV (late systolic MVP) that cause subvalvular PM traction.