[show abstract][hide abstract] ABSTRACT: Surgical ventricular restoration is increasingly applied in patients with ischemic dilated cardiomyopathy. Previous studies show promising results with regard to survival and clinical outcome. However, a comprehensive midterm analysis of this approach on left ventricular (LV) and right ventricular function is not yet available. We investigated biventricular function and clinical status at 6-month follow-up.
We investigated the effects of surgical ventricular restoration on clinical variables, LV volume, right ventricular reverse remodeling, LV dyssynchrony, tricuspid regurgitation, and pulmonary artery pressure in 21 patients with ischemic dilated cardiomyopathy (New York Heart Association class III or IV) who underwent surgical ventricular restoration and coronary artery bypass grafting. Additional surgery included mitral annuloplasty (n = 14) and tricuspid valve annuloplasty (n = 8). Clinical variables (New York Heart Association class, quality-of-life questionnaire, 6-minute hall-walk test) and echocardiographic variables were assessed at baseline and at 6 months.
At 6-month follow-up, all clinical variables were significantly improved. Left ventricular ejection fraction improved from 0.27 +/- 0.10 to 0.36 +/- 0.11 (p < 0.01), LV end-diastolic volume decreased from 248 +/- 78 mL to 152 +/- 50 mL (p < 0.001), and LV end-systolic volume decreased from 186 +/- 77 mL to 101 +/- 50 mL (p < 0.001). Left ventricular dyssynchrony decreased from 61 +/- 41 ms to 12 +/- 12 ms (p < 0.001). Right ventricular annular diameter decreased from 30 +/- 7 mm to 27 +/- 6 mm, right ventricular short-axis from 30 +/- 9 mm to 27 +/- 7 mm, and right ventricular long-axis from 90 +/- 7 mm to 79 +/- 10 mm (all p < 0.05). Finally, significant reductions in severity of tricuspid regurgitation (from 1.3 +/- 1.1 to 0.9 +/- 0.6; p = 0.001) and pulmonary artery pressure (42 +/- 11 mm Hg to 28 +/- 10 mm Hg; p = 0.015) were observed.
Surgical ventricular restoration resulted in improvement of clinical variables, significant LV volume reduction, and reduced LV dyssynchrony at 6-month follow-up. In addition, right ventricular reverse remodeling was noted with reductions in tricuspid regurgitation and pulmonary artery pressure.
The Annals of thoracic surgery 11/2006; 82(5):1721-7. · 3.74 Impact Factor
[show abstract][hide abstract] ABSTRACT: Surgical ventricular restoration aims at improving cardiac function by normalization of left ventricular shape and size. Recent studies indicate that surgical ventricular restoration is highly effective with an excellent 5-year outcome in patients with ischemic dilated cardiomyopathy. We used pressure-volume analysis to investigate acute changes in systolic and diastolic left ventricular function, mechanical dyssynchrony and efficiency, and wall stress.
In 3 patient groups (total, n = 33), pressure-volume loops were measured by conductance catheter before and after surgery. The main study group consisted of 10 patients with ischemic dilated cardiomyopathy (New York Heart Association class III/IV, left ventricular ejection fraction <30%) who had surgical ventricular restoration and coronary artery bypass grafting. In this group, 7 patients had additional restrictive mitral annuloplasty. To assess potential confounding effects of restrictive mitral annuloplasty and cardiopulmonary bypass, we included a group of 10 patients (New York Heart Association class III/IV, left ventricular ejection fraction <30%) who had isolated restrictive mitral annuloplasty and a group of 13 patients with preserved left ventricular function who had isolated coronary artery bypass grafting.
After surgical ventricular restoration, end-diastolic and end-systolic volumes were reduced from 211 +/- 54 to 169 +/- 34 mL (P = .03) and from 147 +/- 41 to 110 +/- 59 mL (P = .04), respectively. Left ventricular ejection fraction (from 27% +/- 7% to 37% +/- 13%, P = .04) and end-systolic elastance (from 1.12 +/- 0.71 to 1.57 +/- 0.63 mm Hg/mL, P = .03) improved. Peak wall stress (from 358 +/- 108 to 244 +/- 79 mm Hg, P < .01) and mechanical dyssynchrony (from 26% +/- 4% to 19% +/- 6%, P < .01) were reduced, whereas mechanical efficiency improved (from 0.34 +/- 13 to 0.49 +/- 0.14, P = .03). End-diastolic pressure increased (from 13 +/- 6 to 20 +/- 5 mm Hg, P < .01), whereas the diastolic chamber stiffness constant tended to be increased (from 0.021 +/- 0.009 to 0.037 +/- 0.021 mL(-1), NS).
Surgical ventricular restoration achieves normalization of left ventricular volumes and improves systolic function and mechanical efficiency by reducing left ventricular wall stress and mechanical dyssynchrony.
The Journal of thoracic and cardiovascular surgery 10/2006; 132(3):610-20. · 3.41 Impact Factor
[show abstract][hide abstract] ABSTRACT: Recent studies show beneficial long-term effects of restrictive mitral annuloplasty in patients with end-stage heart failure. However, concerns are raised about possible adverse effects on early postoperative systolic and diastolic function, which might limit application of this approach in patients with heart failure. Therefore we evaluated the acute effects of restrictive mitral annuloplasty on left ventricular function by using load-independent pressure-volume relations.
In 23 patients (heart failure, n = 10; control, n = 13) we determined left ventricular systolic and diastolic function before and after surgical intervention by means of pressure-volume analysis with a conductance catheter. All patients with heart failure underwent stringent restrictive mitral annuloplasty (2 sizes smaller than the measured size), and 4 received additional coronary artery bypass grafting. Transesophageal echocardiography was used for evaluation of valve repair. Patients with preserved left ventricular function who underwent isolated coronary artery bypass grafting served as control subjects.
Restrictive mitral annuloplasty (ring size, 25 +/- 1) restored leaflet coaptation (8.0 +/- 0.2 mm) with normal pressure gradients (2.9 +/- 1.8 mm Hg). Restrictive mitral annuloplasty did not change cardiac output (5.0 +/- 1.8 to 5.3 +/- 0.9 L/min, P = .516), left ventricular ejection fraction (29% +/- 5% to 32% +/- 8%, P = .315), or end-systolic elastance (0.86 +/- 0.50 to 0.99 +/- 1.05 mm Hg/mL, P = .688). After restrictive mitral annuloplasty, end-diastolic volume tended to decrease (237 +/- 89 to 226 +/- 52 mL, P = .564), whereas end-diastolic pressure remained unchanged (14 +/- 6 to 15 +/- 5 mm Hg, P = .356). Diastolic chamber stiffness tended to increase (0.027 +/- 0.035 to 0.041 +/- 0.047 mL -1 , P = .542) but not significantly. Peak left ventricular wall stress was unchanged (356 +/- 91 to 346 +/- 85 mm Hg, P = .668). Baseline values in the control group were different, but changes in most parameters after surgical intervention showed similar nonsignificant trends.
Mitral valve repair by means of restrictive mitral annuloplasty effectively restores mitral valve competence without inducing significant acute changes in left ventricular systolic or diastolic function in patients with end-stage heart failure.
Journal of Thoracic and Cardiovascular Surgery 08/2005; 130(1):33-40. · 3.53 Impact Factor
[show abstract][hide abstract] ABSTRACT: Recent studies indicate that normothermic cardiopulmonary bypass (CPB) with intermittent antegrade warm blood cardioplegia (IAWBC) may have metabolic and clinical advantages, but limited data exist on its effects on myocardial function. Therefore, we investigated the acute effects of this approach on systolic and diastolic left ventricular function and on chronotropic responses.
In 10 patients undergoing isolated CABG we obtained on-line left ventricular pressure-volume loops using the conductance catheter before and after normothermic CPB with IAWBC. Steady state and load-independent indices of left ventricular function derived from pressure-volume relations were obtained during right atrial pacing (80-100-120 beats/min) to determine baseline systolic and diastolic function and chronotropic responses.
The mean time of CPB was 105+/-36 min (median 103, range 60-167 min) with a mean aortic cross-clamp time of 75+/-27 min (median 69, range 43-129 min). Baseline (80 beats/min) end-systolic elastance (E(ES)) did not change after CPB (1.22+/-0.53 to 1.12+/-0.28 mm Hg/ml, P>0.2), while the diastolic chamber stiffness constant (k(ED)) significantly increased (0.014+/-0.005 to 0.040+/-0.007 ml-1, P=0.018) and relaxation time constant (tau) significantly decreased (61+/-3 to 49+/-2 ms, P=0.004). Before CPB, incremental atrial pacing had no significant effects on E(ES) and tau but significant negative effects on kED (0.014+/-0.005 to 0.045+/-0.012 ml-1, P=0.013). After CPB, atrial pacing had significant positive effects on E(ES), tau and kED (E(ES): 1.12+/-0.28 to 2.60+/-1.54 mm Hg/ml, P=0.021; tau: 49+/-2 to 45+/-2 ms, P=0.009; kED: 0.040+/-0.007 to 0.026+/-0.005 mm Hg, P=0.010), indicating improved systolic and diastolic chronotropic responses.
On-pump normothermic CABG with IAWBC preserved systolic function, increased diastolic stiffness, and improved systolic and diastolic chronotropic responses. Normalization of the chronotropic responses post-CPB is likely due to effects of successful revascularization and subsequent relief of ischemia.
European Journal of Cardio-Thoracic Surgery 04/2005; 27(4):599-605. · 2.67 Impact Factor
[show abstract][hide abstract] ABSTRACT: The treatment of posttraumatic osteomyelitis of the tibia requires meticulous debridement and adequate soft tissue coverage. At our institution, we perform a staged procedure consisting of surgical debridement followed by muscle coverage. If necessary, implantation of a cancellous iliac bone graft was always performed as a three-stage treatment.
We performed a retrospective analysis of 47 patients treated for posttraumatic osteomyelitis of the tibia between 1987 and 1998.
Twenty-two patients originally had a Gustilo grade III fracture, 21 patients had a Gustilo grade I or II or closed fracture, the Gustilo grade was not known for 2 patients, and 2 patients had no fracture. Using the Cierny-Mader classification, most patients had a localized osteomyelitis. To cover the debrided area, 20 pedicled muscle transfers and 28 microvascular free flaps were used; one patient had two localizations of osteomyelitis (both proximal and distal) and received two muscle flaps. Flap failure was 8% and was successfully treated by additional flap coverage in two cases; one was closed by a split skin graft and one was closed by secundum. Twenty-six patients received a cancellous bone graft. During an average follow-up of 94 months, 9% had a recurrence of osteomyelitis for which additional surgical interventions were necessary. Finally, all the infections were eventually cured.
Our staged surgery proved to be an excellent method of treating osteomyelitis after open or closed fractures of the tibia.
The Journal of trauma 04/2004; 56(3):633-42. · 2.35 Impact Factor
[show abstract][hide abstract] ABSTRACT: Mechanical dyssynchrony is an important codeterminant of cardiac dysfunction in heart failure. Treatment, either medical, surgical, or by pacing, may improve cardiac function partly by improving mechanical synchrony. Consequently, the quantification of ventricular mechanical (dys)synchrony may have important diagnostic and prognostic value and may help to determine optimal therapy. Therefore, we introduced new indexes to quantify temporal and spatial aspects of mechanical dyssynchrony derived from online segmental conductance catheter signals obtained during diagnostic cardiac catheterization. To test the feasibility and usefulness of our approach, we determined cardiac function and left ventricular mechanical dyssynchrony by the conductance catheter in heart failure patients with intraventricular conduction delay (n = 12) and in patients with coronary artery disease (n = 6) and relatively preserved left ventricular function. The heart failure patients showed depressed systolic and diastolic function. However, the most marked hemodynamic differences between the groups were found for mechanical dyssynchrony, indicating a high sensitivity and specificity of the new indexes. Comparison of conductance catheter-derived indexes with septal-to-lateral dyssynchrony derived by tissue-Doppler velocity imaging showed highly significant correlations. The proposed indexes provide additional, new, and quantitative information on temporal and spatial aspects of mechanical dyssynchrony. They may refine diagnosis of cardiac dysfunction and evaluation of interventions, and ultimately help to select optimal therapy.
[show abstract][hide abstract] ABSTRACT: Interpretation of perioperative measurements of cardiac function during cardiac surgery is complicated by changes in loading conditions induced by anesthesia, cardiopulmonary bypass (CPB), and the surgical procedure itself. Quantification of left ventricular (LV) function by pressure-volume relations as obtained by the conductance catheter would be advantageous because load-independent indices can be determined. Accordingly, we evaluated methodological aspects of the conductance-catheter technique and documented LV function before and after CPB in eight patients undergoing coronary artery bypass grafting. LV pressure-volume loops by transesophageal echocardiography-guided transaortic application of the conductance catheter were obtained at steady-state and during preload reduction by temporary occlusion of the inferior cava. All patients remained hemodynamically stable, and no complications occurred. Complete data were acquired within 15 min before and after CPB. Cardiac output (5.2 +/- 1.3 L/min to 6.0 +/- 1.4 L/min) and LV ejection fraction (46% +/- 17% to 48% +/- 19%) did not change, but end-diastolic pressure increased significantly after CPB (8 +/- 2 mm Hg to 16 +/- 7 mm Hg; P < 0.05). Load-independent systolic indices remained constant (end-systolic elastance: 1.31 +/- 1.20 mm Hg/mL to 1.13 +/- 0.59 mm Hg/mL). Diastolic function changed significantly after CPB, as the relaxation time constant decreased from 64 +/- 6 ms to 52 +/- 5 ms (P < 0.05) and the chamber stiffness constant increased from 0.016 +/- 0.014/mL to 0.038 +/- 0.016/mL (P < 0.05). We conclude that the conductance catheter method provides detailed data on perioperative myocardial function and may be useful for evaluating the effects of new surgical and anesthetic procedures. IMPLICATIONS: Pressure-volume loops provide on-line quantification of intrinsic systolic and diastolic myocardial function in a load-independent fashion. This study shows the feasibility of perioperative pressure-volume analysis by use of the conductance-catheter method. This method provides detailed data about the immediate effects of surgery and may be used to evaluate complex cardiac procedures.