Minimally invasive mitral valve surgery versus conventional sternotomy mitral valve surgery: A systematic review and meta‐analysis of 119 studies

Abstract

Background and Aim of the Study Whether minimally invasive mitral valve surgery (MMVS) leads to better outcomes remains unclear. We conducted a systematic review and meta‐analysis comparing various MMVS approaches with conventional sternotomy. Methods We searched Cochrane CENTRAL, MEDLINE, EMBASE, ClinicalTrials. gov, and the ISRCTN Register for studies comparing minimally invasive approach (thoracotomy, port access, partial sternotomy, or robotic) with median sternotomy for mitral valve surgery. We performed title and abstract, full‐text screening, and data extraction independently and in duplicate. We pooled data using random effect models. Quality assessment was performed using validated tools. Certainty of evidence was established using the GRADE framework. Results One hundred and nineteen studies (n = 38,106) met eligibility criteria: eight randomized controlled trials (RCTs) and 111 observational studies. MMVS was associated with fewer days in hospital (RCT: MD: −2.2 days, 95% CI, [−3.7 to −0.8]; observational: MD: −2.4 days, 95% CI, [−2.7 to −2.1]). Observational studies suggested that MMVS reduced transfusion requirements with fewer units transfused per patient (MD: −1.2; 95% CI, [−1.6 to −0.9]) and fewer patients transfused (RR, 0.7; 95% CI, [0.6−0.7]). Observational data also suggested lower mortality with MMVS (RR, 0.6; 95% CI, [0.5−0.7], p < .001, I2 = 0%), but this was not corroborated by RCT data. The risk of postoperative mitral regurgitation (≥2+ or requiring re‐intervention) did not differ between the two groups. Conclusions MMVS may be associated with shorter length of hospital stay with no significant difference in short‐term morbidity and mortality. There is a paucity of high‐quality data on the long‐term outcomes of MMVS when compared with conventional sternotomy.

Robotic versus conventional sternotomy mitral valve surgery: a systematic review and meta-analysis

“…Cross clamp and CPB times have consistently been shown to be longer in minimally invasive cardiac surgery procedures when compared to the conventional sternotomy equivalent. Similar to the results seen in the current review, a meta-analysis of 119 studies comparing minimally invasive (not robotic) mitral valve surgery and CSMVS reported that both data from randomized control trials (RCTs) and observational studies showed significantly longer cross clamp and CPB times in the minimally invasive group ( 4 ). This meta-analysis reported a mean difference of only 9 minutes for cross clamp time (P<0.05) and 20 minutes for CPB time (P<0.05) when comparing the data from RCTs.…”

“…These results need to be interpreted with caution, as two of the included studies reporting data on RBC transfusion defined transfusion as greater than or equal to two units of RBCs, therefore introducing significant heterogeneity (19,24). However, reduced rates of RBC transfusion have been consistently reported across most meta-analyses comparing minimally invasive surgery to CSMVS (3)(4)(5).…”

“…The aim of this meta-analysis was to provide the most updated and comprehensive review of all comparative studies in the existing literature comparing RMVS to CSMVS. Several meta-analyses have previously compared minimally invasive mitral valve surgery (mini-thoracotomy, mini-sternotomy and/or thoracoscopic) to CSMVS (3)(4)(5)(31)(32)(33). However, only two previous meta-analyses have attempted to analyze RMVS and CSMVS (7,8), both of which had their own limitations as mentioned above.…”

“…The various techniques developed for performing minimally invasive mitral valve surgery range from partial sternotomy, port-access thoracoscopic, right mini-thoracotomy, and RMVS (2). Although the benefits of minimally invasive surgery over CSMVS are incompletely understood, they are suggested to include better cosmesis, shorter lengths of hospital stay and use of fewer blood products without a significant difference in morbidity and mortality compared to conventional sternotomy (3)(4)(5). The downfalls of these more minimally invasive procedures have been consistently related to prolonged operative times which have been attributed to the steep learning curve that minimally invasive mitral valve surgery entails (6).…”

Minimally invasive mitral valve surgery with or without robotics: Examining the evidence

“…This trend has been encouraged by favorable short‐term outcomes of both MIMVS approaches reported in several meta‐analysis and retrospective studies in high‐volume centers. Almost all the studies comparing sternotomy versus mini‐thoracotomy, 7–11 or sternotomy versus robotic‐assisted MIMVS, 12–18 demonstrated similar findings in that both MIMVS approaches provided better short‐term outcomes including shorter hospital stay, less need for blood transfusions, lower incidence of postoperative atrial fibrillation, and earlier return to normal activity despite the longer procedure time compared to sternotomy. Mid‐term outcomes of mini‐thoracotomy 8 and robotic‐assisted MIMVS 13 were also equivalent to a sternotomy approach.…”