Autschbach et al. reported the early Leipzig experience with robot-assisted minimally invasive mitral valve repair surgery [9]. Of the 167 patients considered for analysis, 152 underwent a long-instrument mitral valve repair using AESOP™ (Intuitive Surgical, Mountain View, CA), a voice-controlled video-guided robotic arm, while 15 had repairs performed using the da Vinci™ tele-manipulation system. From the latter group 13 had successful repairs, while two required a re-operation. The authors stated that they had carefully selected the repairs operated with da Vinci™, leaving more complex repairs for standard minimally invasive approaches.

Tatooles et al. reported their experience in 25 patients and demonstrated excellent results with no mortality, device-related complications, strokes or re-operations for bleeding [10]. One patient had a transient ischemic attack 7 days after surgery. Cardiopulmonary bypass and cross-clamp times were 126.6 ± 25.7 min and 87.7 ± 20.9 min, respectively. Eighty-four percent of patients were extubated in the operating room and eight were discharged home within 24 h with a mean hospital stay of 2.7 days. However, the rate of hospital readmissions was 28 %. Two patients required a re-operation for recurrent mitral regurgitation, one at 3 days post-operatively and the other at 40 days. Echocardiograms performed at 30 days post-operatively showed that 96 % had less than or equal to 1+ regurgitation.

Jones et al. reported their series of 32 patients, who underwent a da Vinci™ mitral valve repair in a community hospital setting [11]. They performed concomitant procedures in five patients (tricuspid valve repair, n = 3; MAZE atrial fibrillation ablation, n = 2). There were two deaths, neither of which could be attributed to the robotic surgical system. Complications included reoperations for repair failure (n = 3), stroke (n = 1), and pulmonary embolism (n = 1).

McClure et al. reported the first series of da Vinci™ assisted mitral valve repairs in Canada [12]. Ten patients with normal left ventricular function and severe mitral regurgitation underwent mitral valve repairs. All but one patient had a successful repair. Because of persistent regurgitation, this patient required conversion to a valve replacement. No deaths, strokes, or conversions to a sternotomy were recorded.

In a non-randomized, single-surgeon experience, Woo et al. compared outcomes in 64 patients, who were eligible for either a sternotomy (n = 39) or a minimally invasive da Vinci™ repair (n = 25) [13]. The two groups had an equal number of mitral repairs. Cross-clamp and cardiopulmonary bypass times were longer in the minimally invasive group (151 vs. 110 min and 239 vs. 162 min, respectively). Packed red blood cell transfusion volume was lower in the robot-assisted patients (2.8 vs. 5.0 units) as was the mean post-operative length of hospital stay (7.1 vs. 10.6 days).

Folliguet et al. reported 25 patients undergoing a posterior leaflet mitral valve repair with da Vinci™ and matched them retrospectively to 25 patients who had the same repair via a sternotomy [14]. While longer cross-clamp and cardiopulmonary bypass times were noted for the robotic group (96.1 vs. 69.6 min and 122.1 vs. 85.7 min, respectively), hospital stays were shorter (7 days vs. 9 days, p = 0.05). Indices of valve repair success were comparable between the two groups.

Murphy et al. reported 127 robotic mitral repairs of which five were converted to a median sternotomy [15]. Seven patients underwent a mitral valve replacement and 114 had mitral valve repairs. Complications included one in-hospital and one late mortality, a 1.6 % stroke incidence, and 17 % new-onset of atrial fibrillation. Post-discharge echocardiograms were collected in 98 patients with a mean follow-up of 8.4 months. In 96.2 % of patients no more than a 1+ residual MR leak persisted. This series demonstrated that robotic mitral valve surgery is safe with excellent short-term results and good mid-term durability.

In 2008 Chitwood et al. reported the largest early single center experience of 300 da Vinci™ mitral repairs with 0.7 % and 2.0 % 30-day and late mortalities, respectively [16]. No sternotomy conversions or mitral valve replacements were required. Immediate post-repair echocardiograms showed that 98 % of patients had either no or trivial residual mitral regurgitation. Complications included two (0.7 %) strokes, two (0.7 %) transient ischemic attacks, three (1.0 %) myocardial infarctions, and seven (2.3 %) re-operations for bleeding. The mean hospital stay was 5.2 ± 4.2 (SD) days and 16 (5.3 %) patients required a re-operation at a mean of 319 ± 327 days from the original operation. Mean post-operative echocardiographic follow-up at 815 ± 459 days demonstrated that 92.4 % had none, trace, or mild recurrent mitral regurgitation. Five-year Kaplan-Meier survival was 96.6 ± 1.5 % with a 93.8 ± 1.6 % freedom from re-operation. That same year Chitwood et al. examined outcomes in patients having a robotic mitral repair for either anterior leaflet prolapse or Barlow’s disease and found the technique to be safe and feasible [17].

In 2010 Cheng et al. reported their initial 120 robotic mitral valve repairs, the first 74 of which were performed using the first-generation da Vinci™ robot and the last 46 of which were performed using the latest da Vinci ™ Si HD device, a third generation surgical robot [18].They had one hospital mortality (0.8 %), and five patients (4.2 %) required an immediate mitral valve replacement for a failed repair. One patient underwent a mitral valve re-repair on the second post-operative day. Median trans-thoracic echocardiographic follow-up was 321 days (107 of 115 patients remaining). Of these 89 %, 8.4 %, and 2.8 % had none/mild, moderate, or severe mitral severe mitral regurgitation, respectively. One patient with severe regurgitation underwent a valve replacement, and the other two were managed medically. All in-hospital valve repair failures occurred in the early series using the older model da Vinci™ robot.

In 2011 Mihaljevic et al. compared results from propensity matched posterior leaflet prolapse mitral repairs with more traditional approaches (sternotomy [n = 114], hemi-sternotomy [n = 270)], and mini-thoracotomy [n = 114]) to 261 similar anatomic repairs with da Vinci™ [19]. There were no in hospital deaths. Moreover neurological, pulmonary, and renal complications did not differ between cohorts. However, patients in the robotic group had shorter hospital stays, despite longer perfusion, cardiac arrest, and overall operative times. Effective and quality mitral repairs were similar in both groups. Robotic mitral repairs were deemed safe and effective. More recently, Mihaljevic et al. have published a comparison of robotic mitral valve repair techniques, comparing robotic neochordal versus robotic resectional techniques in patients with posterior mitral valve leaflet disease [20]. They found that while both techniques had similar residual mitral regurgitation, robotic neochordal techniques were associated with shorter operative times and a lower occurrence of systolic anterior motion.

In 2011, Suri et al. compared early results of robotic versus open mitral valve repair in patients with mitral valve prolapse [21]. Of 745 consecutive cases of either open or robotic mitral valve repairs, 95 propensity-matched pairs were identified. Overall rates of post-operative adverse events were similar between the two groups. While median cross-clamp and total bypass times were longer among patients in the robotic group, these patients were also more likely to experience shorter post-operative ventilation time, length of stay in intensive care unit, and overall hospital length of stay.

In 2012 Nifong et al. updated the East Carolina University series and included 540 consecutive cases (including those that had been done as part of the inaugural FDA trial) with either 3+ (7.4 %) or 4+ (92.6 %) mitral regurgitation who underwent robotic mitral valve repairs with or without concomitant robotic cryoMAZE ablation for atrial fibrillation [22]. Postoperative transesophageal echocardiography showed that 447 (82.8 %) had no mitral insufficiency, while 80 (14.8 %) had trace, 12 (2.2 %) had mild, and 3 (0.6 %) had moderate post-repair mitral regurgitation. There were two early deaths (0.4 %), and the late mortality was 1.7 % (n = 9) with six patients expiring of non-cardiac causes. The mean hospital stay length was 5.6 ± 4.0 days (SD), and reoperations were required in 2.9 % of patients at 303 ± 281 (15–946) days following surgery. Of those undergoing a concomitant cryoablation, 96.5 % were free from atrial fibrillation and were off warfarin and anti-arrhythmic drugs at follow-up.

In 1998, Loulmet et al. demonstrated in two patients the feasibility of performing a TECAB on an arrested heart. Using the first generation da Vinci™, they mobilized the left ITA (LITA) and grafted the left anterior descending (LAD) coronary artery robotically [26].

In 2000, Falk et al. reported 22 TECAB operations of which four were converted to a mini-thoracotomy for either anastomotic bleeding or other graft related issues. In the remaining 18 patients, grafts were patent by angiography at 3 months with no major complications. The same group reported the first off-pump TECAB using an endoscopic stabilizing device [27, 28].

In 2001, Mohr et al. reported 131 robotically assisted CABG cases, of which 81 had a robotically assisted ITA takedown followed by a minimally invasive direct coronary anastomosis. Of these 15 had an ITA to LAD anastomosis, performed via a sternotomy. The remaining 35 patients underwent an attempted TECAB procedure [29]. post-operative graft patency in there TECAB group was 96.3 % completed successfully in 24 of 35 cases, with the majority of intra-operative conversions occurring in the first half of the series.

In 2002 Dogan et al. reported 45 arrested heart TECAB procedures, in which eight patients underwent two-vessel revascularization with both right and left ITAs [30]. The initial conversion rate was 22 % and fell to 5 % in the last 20 patients. The mean operative time for a single-vessel TECAB was 4.2 ± 0.4 h. Cardiopulmonary bypass (CPB) and aortic cross-clamp (XC) times were 136 ± 11 and 61 ± 5 min, respectively.

Subramanian et al. performed multi-vessel revascularizations (mean grafts = 2.6) in 30 patients, using robot harvested ITAs [31]. Either a mini-thoracotomy or the trans-abdominal approach was used. Twenty-nine (97 %) patients were extubated in the operating room, and 77 % were discharged within 48 h with two requiring hospital readmission. One patient was converted to a sternotomy, and there was no operative mortality.

Srivastava et al. reported 150 patients, having combined robot-assisted bilateral ITA grafts and an off-pump CABG via a mini-thoracotomy [32]. Two patients presented later with chest pain secondary to graft failure. In both cases, a percutaneous intervention was successful in resolving the occlusion. In 55 patients all 136 grafts were patent at 3 months by computed tomography angiography.

Argenziano et al. reported an FDA multi-center Investigational Device Exemption trial in 2006 [33]. Ninety-eight patients requiring single-vessel LAD revascularization were enrolled at 12 centers with 13 patients (13 %) excluded intraoperatively for either a failed femoral arterial cannulation or an inadequate intra-thoracic working space. In the remaining 85 TECAB patients, CPB and arrest times were 117 ± 44 and 71 ± 26 min, respectively, and the hospital length of stay was 5.1 ± 3.4 days. There were five (6 %) conversions to a sternotomy and no deaths or strokes. There was one early reintervention and one myocardial infarction. In 76 patients angiography after 3 months revealed either a significant anastomotic stenosis (>50 %) or occlusions in six patients (7.1 %). Therefore, the overall freedom from either reintervention or angiographic failure was 91 % at 3 months. Based largely on this study, the United States FDA approved da Vinci™ robot for coronary revascularization.

In 2007, de Cannière et al. reported the largest multi-center experience at that time, which involved five European institutions and 228 TECAB patients (on-pump, n = 117; off-pump, n = 111) [34]. The overall mortality was 2.1 % with a conversion rate of 28 %, which decreased with time and did not affect clinical outcomes adversely. Procedural efficacy was 97 % at 6 months, as defined either by angiographic patency and/or absence of ischemia during stress electrocardiography. The incidence of major adverse cardiac events within 6 months was 5 %. Target vessel re-intervention was slightly higher for both on- and off-pump procedures, compared to those for open procedures reported by the Society of Thoracic Surgeons National Database.

In 2009, Caynak et al. published a series of 196 robot-assisted revascularization operations [35]. The ITAs were harvested robotically with the anastomoses performed via a mini-thoracotomy (single-vessel revascularization: n = 118; multi-vessel revascularization: n = 74). Freedom from ischemic symptoms was 98.2 % at a mean of 22 ± 3 months and graft patency was 96.4 %.

In 2009, Bonatti et al. reported 100 TECAB operations in which the ITA was anastomosed to the LAD using the da Vinci™ system [36]. The overall series was divided into four operative patient groups (1 = 1–25; 2 = 26–50; 3 = 51–75; and 4 = 76–100). Median operative times decreased from 400 min in group 1 to 272 min in group 4. Similarly, the number of conversions decreased from seven (28 %) in group one to one (4 %) in group four. They had no peri-operative mortality. Five-year survival, freedom from angina, and avoidance of both major adverse cardiac and cerebrovascular events were 100, 91, and 89 %, respectively. They compared quality of life for TECAB to standard CABG patients and found that TECAB patients who did not have an intra-operative conversion had significantly higher scores, regarding pain and physical health. Moreover, they had shorter hospital stays and significantly better return to daily activities [33].

In 2013, Bonatti et al. reported on a series of 500 TECAB cases performed between 2001 and 2011 (single: n = 334; double: n = 150; triple: n = 15; quadruple: n = 1) [37]. They reported a 95 % freedom from major adverse cardiac and cerebral events, major vascular injury and long-term ventilation. Intra-operative conversion to larger thoracic incisions were required in 49 (10 %) cases. The median operative time was 305 min (112–1,050 min), and the mean lengths of stay in the intensive unit (ICU) and in hospital were 23 h (11–1,048 h) and 6 days (2–4 days), respectively.

The centerpiece of hybrid coronary revascularization is a robotic ITA anastomosis to the LAD followed by either contemporaneous or interval coronary stenting to complete the revascularization strategy. Recent work by Katz et al. demonstrated that this approach could be accomplished with no mortality, low peri-operative morbidity, and excellent 3-month angiographic ITA patency (96.3 %) (See Chap.​ 14) [38]. Kiaii et al. reported 91 % ITA-LAD patency at 9 months for simultaneous integrated coronary revascularization, using robot-enhanced techniques [39]. However, Kappert et al. showed that after a robotic TECAB 5-year freedom from LAD reintervention was only 87.2 %. Albeit data from the early TECAB era, improvement in these results was mandated and perhaps could be accomplished by using more advanced robotic technology [40]. More recently, Gao et al. corroborated these results in 42 patients undergoing hybrid revascularization [41]. Similarly, Bonatti et al. found that in 226 patients who underwent hybrid coronary interventions on an intention-to-treat basis, hospital mortality was 1.3 % 5-year survival was 92.9 % and 5-year freedom from re-intervention was 97.3 % for bypass grafts and 85.8 % for percutaneous coronary intervention targets [42]. Refinements in anastomotic technology, endoscopic stabilization, and target vessel identification systems all should facilitate routine TECAB. However, similar to daVinci™ assisted mitral valve repair, long-term follow-up of these types of coronary revascularization procedures is needed to determine if they will have comparable patency to those performed through a traditional sternotomy.