Markus Czesla

Minimal invasive mitral valve repair for mitral regurgitation: results of 1339 consecutive patients

OBJECTIVE Some have expressed concern that minimal invasive mitral valve (MV) repair may not meet the standard of open surgical techniques. We therefore reviewed our results for minimal invasive MV repair for mitral regurgitation (MR). MATERIAL AND METHODS Between March 1999 and February 2007, a total of 1536 consecutive patients underwent minimal invasive MV surgery for MR at our institution using a right lateral mini-thoracotomy and femoral cannulation for cardiopulmonary bypass. Of these, a total of 1339 (87.2%) patients underwent MV repair and these form the focus of this study. The mean grade of preoperative MR was 3.3+/-0.6, age was 60.3+/-12.7 years, ejection fraction was 59.2+/-15.1% and 819 patients (61.2%) were male. RESULTS The procedure was successfully performed in all but four patients (0.3%) who required intraoperative conversion to full sternotomy. MV repair techniques consisted of ring annuloplasty with or without chordae-replacement or Carpentier-type leaflet resection. Concomitant procedures consisted of atrial fibrillation ablation in 351 patients (26.2%), tricuspid valve surgery in 80 patients (6.0%), and patent foramen ovale/atrial septal defect closure in 88 patients (6.6%). Mean duration of CPB was 121+/-38min and mean aortic cross-clamp time was 70+/-32min. Thirty-day mortality was 2.4%. Follow-up was performed in 99% of patients at an average of 28.1+/-23.9 months postoperatively. The Kaplan-Meier estimate for survival at 5 years was 82.6% (95% CI: 78.9-85.7%) and for freedom from MV reoperation was 96.3% (95% CI: 94.6-97.4%). CONCLUSIONS Minimal invasive MV repair, along with certain concomitant procedures, can be performed in the vast majority of patients with MR. Our large series demonstrates that these procedures can be performed with low perioperative complication rates and very good durability.

How does the use of polytetrafluoroethylene neochordae for posterior mitral valve prolapse (loop technique) compare with leaflet resection? A prospective randomized trial

OBJECTIVE Mitral valve surgery for posterior mitral leaflet prolapse consists mostly of leaflet resection, but implantation of premeasured polytetrafluoroethylene neochordae (ie, loops) is another option. The aim of this prospectively randomized trial was to determine how preservation of leaflet structure in combination with premeasured neochordae compares with the widely adopted technique of leaflet resection. METHODS A total of 129 patients with severe mitral regurgitation, with a mean mitral regurgitation grade of 3.6 +/- 0.6, underwent minimal invasive mitral valve surgery through a right lateral mini-thoracotomy. The mean age was 59.5 +/- 12 years, 90 patients were male, the mean preoperative ejection fraction was 65% +/- 8%, and the mean New York Heart Association functional class was 2.1 +/- 0.7. Posterior mitral leaflet prolapse was diagnosed in all patients. Randomization was performed preoperatively, and crossover was allowed if the surgeon deemed it medically necessary. Crossover from resection to loops occurred in 9 patients, and crossover from loops to resection occurred in 3 patients. RESULTS Mitral valve repair was accomplished in all patients (n = 129, 100%), and all patients received an annuloplasty ring. The mean number of loops implanted on the posterior mitral leaflet was 3.2 +/- 0.9, with a mean length of 13.3 +/- 2.2 mm. The mean duration of cardiopulmonary bypass was 135 +/- 37 minutes and the mean aortic crossclamp time was 82 +/- 26 minutes in all patients, with no significant difference between groups. Intraoperative transesophageal echocardiography showed a significantly longer line of mitral valve leaflet coaptation after implantation of loops (7.6 +/- 3.6 mm) than after resection (5.9 +/- 2.6 mm; P = .03). Thirty-day mortality was 1.6% for the entire group (2/129), with both deaths occurring in the loop group. Cause of death was massive pulmonary embolism in 1 patient and acute right heart failure in 1 patient. Early and mid-term echocardiographic follow-up revealed excellent valve function in the majority of patients, with no significant difference in mitral orifice area (3.6 +/- 1.0 cm(2) vs 3.7 +/- 1.1 cm(2), P = .4). CONCLUSION Both repair techniques for posterior mitral leaflet prolapse are associated with excellent results and appear comparable in the early postoperative course. The loop technique, however, results in a significantly longer line of leaflet coaptation and may therefore be more durable. Longer follow-up is required.

Approaching a Paradigm Shift: Endoscopic Ablation of Lone Atrial Fibrillation on the Beating Heart

BACKGROUND Percutaneous catheter ablation has been the preferred treatment strategy for many patients with symptomatic drug-refractory atrial fibrillation (AF). However, incomplete ablation lines and varying success rates remain a problem in certain subgroups. This article evaluates the feasibility and efficacy of endoscopically performed left atrial ablation in patients with lone AF. METHODS Epicardial bipolar radiofrequency ablation was performed on the beating heart through a bilateral endoscopic approach in 89 consecutive patients with lone AF. This included isolation of the pulmonary veins using a clamp; isolation of the posterior left atrial wall, including a trigonal line to the aortic noncoronary sinus using a linear ablation device; and resection of the left atrial appendage (LAA). Preoperative, perioperative, and postoperative data were collected prospectively and included questionnaires and 24-hour Holter monitoring at 6 and 12 months and annually thereafter. RESULTS Mean follow-up was 12±6 months (range, 4-28 months). No patients were lost to follow-up. Mean duration of AF was 6.4±5.7 years, with 35% paroxysmal AF and 65% persistent or long-standing persistent AF. Mean operation time was 180±43 minutes. There were no deaths, no conversion to sternotomy, and no early or late stroke. Freedom from AF was 88%, 90%, and 90% at 6, 12, and 24 months, respectively. Freedom from AF without antiarrhythmic drugs was 71%, 82%, and 90% at 6, 12, and 24 months, respectively. CONCLUSIONS Endoscopic radiofrequency ablation on the beating heart reveals high success rates with low procedure-related morbidity. For improvement of future treatment strategies, a randomized trial is advisable to compare this procedure with catheter ablation in certain patient subgroups.

Ablation of Ganglionic Plexi During Combined Surgery for Atrial Fibrillation

PURPOSE Recent investigations into the treatment of atrial fibrillation have suggested improved outcomes after concomitant pulmonary vein isolation (PVI) and ganglionic plexi (GP) ablation. We investigated the impact of left atrial ablation with substrate modification (left atrial maze) or epicardial PVI, combined with GP mapping and ablation, in patients with paroxysmal or longstanding persistent atrial fibrillation undergoing additional off-pump or on-pump cardiac surgery. DESCRIPTION Twelve patients aged 74.9 +/- 3.8 years, with atrial fibrillation for 4.5 +/- 1.5 years, underwent left atrial maze or epicardial PVI, along with GP mapping and ablation during coronary bypass grafting with or without valve surgery. The GP mapping used high-frequency bipolar stimulation. The GP ablation and PVI were achieved using bipolar radiofrequency ablation. Conduction block was confirmed by pacing. EVALUATION At 1-year follow-up, 83% of patients were in sinus rhythm. Echocardiography confirmed satisfactory bi-atrial contraction. Exercise-induced heart rate variability was appropriate. There were no early deaths. CONCLUSIONS Epicardial PVI, left atrial maze, GP mapping, and ablation for the treatment of atrial fibrillation can be effectively and safely performed during surgery for other cardiac pathologies.

Dynamic annuloplasty for mitral regurgitation

OBJECTIVE The MiCardia DYANA annuloplasty system (MiCardia Corp, Irvine, Calif) is a nitinol-based dynamic complete ring that allows modification of the septal-lateral diameter under transesophageal echocardiography guidance in the loaded beating heart after mitral valve repair. Shape alteration is induced by radiofrequency via detachable activation wires. This multicenter study reports the first human experience with this device. METHODS Patients (n = 35, 67 ± 8 years) with degenerative (n = 29), functional/ischemic (n = 5), or rheumatic (n = 1) mitral regurgitation underwent mitral valve repair using the new device. We analyzed the occurrence of death, endocarditis, ring dehiscence, systolic anterior motion, thromboembolism, pulmonary edema, heart block, ventricular arrhythmia, hemolysis, or myocardial infarction at 30 days (primary end point) and 6 months (secondary end point) postprocedure. RESULTS All patients exhibited mitral regurgitation of 2 or less early postoperatively and at 6 months follow-up. In 29 patients, the initial mitral valve repair result was satisfactory and no ring activation was required. In 6 patients, the nitinol-based ring was deformed intraoperatively postrepair with further improvement of mitral regurgitation in all cases (preactivation: 0.9 ± 0.2, postactivation: 0.2 ± 0.3; P = .001). One death (2.9%, multisystem organ failure, non-device related), 2 ventricular arrhythmias (5.7%), and 1 heart block (2.9%) occurred, all in the first 30 days after surgery. No additional major adverse clinical events occurred later than 1 month postprocedure (total observed major adverse clinical event rate 11.5%). CONCLUSIONS The implantation of the new dynamic annuloplasty ring allows for safe mitral valve repair. The option of postrepair modification of the septal-lateral diameter by radiofrequency may further optimize repair results.

Efficacy and safety of various energy sources and application techniques for the surgical treatment of atrial fibrillation

We investigated efficacy and safety of different energy sources and application techniques for the treatment of atrial fibrillation in an experimental acute sheep model. In particular, we focused on thermal damage to the adjacent structures and tissues. We also attempted to evaluate the efficacy of different application techniques such as endocardial or epicardial approaches. Overall 64 young Merino sheep were examined. It could be shown that endocardial ablation with different energy sources on cardiopulmonary bypass consistently caused histomorphologically and electrophysiologically transmural lesions. Depending on the energy source, different amounts of endocardial damage were induced. Cryoapplication produces the smallest endocardial laceration without thrombus formation. Dry radiofrequency energy and microwave produced very wide and diffuse endocardial damage with carbonisation and disruption of the endothelium. Epicardial ablation on a beating heart (off-pump) with bipolar radiofrequency was consistently effective. Due to the energy flow between the two jaws of the bipolar clamp, no collateral damage was observed. All other energy sources were unable to produce transmural lesions epicardially (off-pump) because the nearby blood flow rewarmed or recooled the myocardium and caused the so called “heat sink phenomenon”. Depending on the energy source, different histomorphological changes in the esophagus could be observed. Changes in intraluminal-measured esophageal temperatures were not observed during ablation.ZusammenfassungIm Rahmen der vorliegenden tierexperimentellen Arbeit wurden verschiedene operative Ablationsverfahren zur Behandlung des Vorhofflimmerns hinsichtlich ihrer Sicherheit und Effektivität im Schafmodell evaluiert. Insbesondere wurden angrenzende Gewebe und Organstrukturen hinsichtlich thermischer Schädigungen untersucht. Das Ziel der vorliegenden Arbeit ist die Differenzierung und die Effektivitätsprüfung der endokardialen und der epikardialen Applikationsform. Die Untersuchungen wurden an insgesamt 64 jungen Merino Schafen durchgeführt. In diesem Tiermodell konnte aufgezeigt werden, dass die endokardiale Ablationstechnik unter Einsatz der HLM effektiv ist und histomorphologisch sowie elektrophysiologisch eine transmurale Läsion bewirkt. In Abhängigkeit von der Energieform zeigten sich unterschiedliche Formen der Degeneration des Endokards. Das geringste endotheliale Trauma wird durch die Kryoapplikation verursacht, wobei hier auch keine Thrombusformationen beobachtet wurden. Breite und massive Endothelschäden mit Karbonisationen wurden bei den nicht gekühlten unipolaren Hochfrequenzenergien und der Mikrowelle beobachtet. Die epikardialen Ablationen mittels bipolarer Hochfrequenzenergie am schlagenden Herzen ohne Einsatz der Herz-Lungen-Maschine waren stets effektiv. Der Energiefluss geht hierbei von einer Scherenbranche zur anderen, somit ist eine thermische Schädigung der umliegenden Strukturen nahezu ausgeschlossen. Die epikardialen Ablationen mit anderen Energiequellen sind aufgrund des kühlenden, bzw. aufwärmenden Effektes des Blutflusses nicht effektiv. Unterschiedliche histomorphologische Läsionen im Bereich des Ösophagus zeigten sich in Abhängigkeit von der Energieform. Temperaturveränderungen während der Ablation konnten im Ösophagus endoluminal nicht beobachtet werden.

Experimentelle Evaluierung verschiedener Energiequellen und Applikationsverfahren zur chirurgischen Therapie des Vorhofflimmerns

We investigated efficacy and safety of different energy sources and application techniques for the treatment of atrial fibrillation in an experimental acute sheep model. In particular, we focused on thermal damage to the adjacent structures and tissues. We also attempted to evaluate the efficacy of different application techniques such as endocardial or epicardial approaches. Overall 64 young Merino sheep were examined. It could be shown that endocardial ablation with different energy sources on cardiopulmonary bypass consistently caused histomorphologically and electrophysiologically transmural lesions. Depending on the energy source, different amounts of endocardial damage were induced. Cryoapplication produces the smallest endocardial laceration without thrombus formation. Dry radiofrequency energy and microwave produced very wide and diffuse endocardial damage with carbonisation and disruption of the endothelium. Epicardial ablation on a beating heart (off-pump) with bipolar radiofrequency was consistently effective. Due to the energy flow between the two jaws of the bipolar clamp, no collateral damage was observed. All other energy sources were unable to produce transmural lesions epicardially (off-pump) because the nearby blood flow rewarmed or recooled the myocardium and caused the so called “heat sink phenomenon”. Depending on the energy source, different histomorphological changes in the esophagus could be observed. Changes in intraluminal-measured esophageal temperatures were not observed during ablation.ZusammenfassungIm Rahmen der vorliegenden tierexperimentellen Arbeit wurden verschiedene operative Ablationsverfahren zur Behandlung des Vorhofflimmerns hinsichtlich ihrer Sicherheit und Effektivität im Schafmodell evaluiert. Insbesondere wurden angrenzende Gewebe und Organstrukturen hinsichtlich thermischer Schädigungen untersucht. Das Ziel der vorliegenden Arbeit ist die Differenzierung und die Effektivitätsprüfung der endokardialen und der epikardialen Applikationsform. Die Untersuchungen wurden an insgesamt 64 jungen Merino Schafen durchgeführt. In diesem Tiermodell konnte aufgezeigt werden, dass die endokardiale Ablationstechnik unter Einsatz der HLM effektiv ist und histomorphologisch sowie elektrophysiologisch eine transmurale Läsion bewirkt. In Abhängigkeit von der Energieform zeigten sich unterschiedliche Formen der Degeneration des Endokards. Das geringste endotheliale Trauma wird durch die Kryoapplikation verursacht, wobei hier auch keine Thrombusformationen beobachtet wurden. Breite und massive Endothelschäden mit Karbonisationen wurden bei den nicht gekühlten unipolaren Hochfrequenzenergien und der Mikrowelle beobachtet. Die epikardialen Ablationen mittels bipolarer Hochfrequenzenergie am schlagenden Herzen ohne Einsatz der Herz-Lungen-Maschine waren stets effektiv. Der Energiefluss geht hierbei von einer Scherenbranche zur anderen, somit ist eine thermische Schädigung der umliegenden Strukturen nahezu ausgeschlossen. Die epikardialen Ablationen mit anderen Energiequellen sind aufgrund des kühlenden, bzw. aufwärmenden Effektes des Blutflusses nicht effektiv. Unterschiedliche histomorphologische Läsionen im Bereich des Ösophagus zeigten sich in Abhängigkeit von der Energieform. Temperaturveränderungen während der Ablation konnten im Ösophagus endoluminal nicht beobachtet werden.

Safety and feasibility of a novel adjustable mitral annuloplasty ring: a multicentre European experience

OBJECTIVES Recurrent mitral regurgitation is a significant problem after mitral valve repair in patients with functional valve disease. We report the safety and feasibility of a novel adjustable mitral annuloplasty device that permits downsizing of the anterior–posterior diameter late after initial surgery. METHODS In this multicentre, non-randomized, observational register, patients with moderate or severe mitral regurgitation undergoing surgical mitral valve repair with the MiCardia EnCorSQ™ Mitral Valve Repair system were evaluated. Patient characteristics, operative specifications and results as well as postoperative follow-up were collected for all five centres. RESULTS Ninety-four patients with a median age of 71 (64–75) years (EuroSCORE II 6.7 ± 6.3; 66% male, 48% ischaemic MR, 37% dilated cardiomyopathy and 15% degenerative disease) were included. Operative mortality was 1% and the 1-year survival was 93%. Ring adjustment was attempted in 12 patients at a mean interval of 9 ± 6 months after surgery. In three of these attempts, a technical failure occurred. In 1 patient, mitral regurgitation was reduced two grades, in 2 patients mitral regurgitation was reduced one grade and in 6 patients, mitral regurgitation did not change significantly. The mean grade of mitral regurgitation changed from 2.9 ± 0.9 to 2.1 ± 0.7 (P = 0.02). Five patients were reoperated after 11 ± 9 months (Ring dehiscence: 2; failed adjustment: 3). CONCLUSION We conclude that this device may provide an additional treatment option in patients with functional mitral regurgitation, who are at risk for reoperation due to recurrent mitral regurgitation. Clinical results in this complex disease were ambiguous and patient selection seems to be a crucial step for this device. Further trials are required to estimate the clinical value of this therapeutic concept.

How to establish video assisted, minimally invasive mitral valve surgery

Changing the surgical routine from standard sternotomy to mini-thoracotomy can prove more challenging than may be first considered. This article describes the advantages and disadvantages, as well as technical details and potential pitfalls, on the way to establishing minimally invasive mitral valve (MV) surgery. A smaller cut means a smaller scar. Todays patients show an increasing awareness of invasive methods and procedures. Why saw the sternum into pieces instead of making a 5 cm long incision in the submammary crease? Certainly there are cosmetic issues to consider, especially in younger patients and women, but the major advantages reach far beyond the surface of the skin. The right lateral mini-thoracotomy approach permits a straight and direct view of the MV and hence provides a significantly improved assessment of its malfunction and critical application of various repair techniques. In patients who require redo MV surgery and have undergone prior MV repair via sternotomy, access to the MV through a lateral thoracotomy approach saves the surgeon from undertaking a difficult dissection and hence lowers the risks of potential harm to the heart and its surrounding structures. The reduction of mortality and morbidity as well as overall surgical trauma, and the more rapid recovery of patients, have been demonstrated in several studies.1–4 However, this procedure requires an entirely different surgical skill set. Integrating video images into the visual feedback, and using long instruments in a narrow and deep surgical field, certainly requires intense training. The technique needs to be performed with perfection in order to minimise certain risks associated with minimally invasive MV surgery, particularly perioperative strokes, aortic dissections, and vascular complications of the femoral vessels.4 The surgeon must be mindful of the consequences of retrograde perfusion when choosing …

Safeguards and pitfalls in minimally invasive mitral valve surgery

Minimally invasive mitral valve surgery has been established in many institutions worldwide. Appropriate indications and patient selection for this procedure must be based on a thorough understanding of its limitations and specific pitfalls. Particular risks can be minimized with careful attention to detail when planning and performing the surgery. The following chapter offers a stepwise description of the procedure; we point out particular advantages, discuss our rationale for certain steps, as well as focus on potential dangers of minimally invasive mitral valve surgery. Several graphics have also been provided to illustrate our approach and demonstrate important structural and anatomical concepts of the mitral valve apparatus.