Intraoperative transesophageal echo-Doppler evaluation of stentless aortic xenografts. Incidence and significance of moderate gradients.

BACKGROUND: The aim of this study was to assess the utility of intraoperative transesophageal echocardiography (TEE) in the evaluation of patients undergoing aortic valve replacement with the CryoLife-O'Brien (CLOB) Stentless Porcine Aortic Bioprosthesis. METHODS: Between May 1994 and March 1995, 26 patients (15 men, mean age 68.4+/-10.78 years) had a CLOB valve in the aortic position. Transprosthetic gradients and valve regurgitation were detected by intraoperative TEE. Prosthetic regurgitation and transvalvular gradients were evaluated at six-month intervals using transthoracic echo-Doppler (TTE). RESULTS: The majority of implants resulted in low gradients (83.7%), with only four patients exhibiting a moderate gradient (15.3%). Color flow Doppler imaging showed central aortic regurgitation in only four of 25 patients (trivial, n=4; mild, n=1). There was one paravalvular leak (trivial, n=1). At follow-up examination (mean 37+/-12 months), 24 of 25 patients exhibited low mean gradients (7.25+/-2.81 mmHg). At follow-up one patient who had low velocities in the LVOT at perioperative evaluation exibited a moderate gradient (45 mmHg) with an effective orifice area of 0.8-0.9 cm(2). CONCLUSIONS: Intraoperative TEE was effective in assessing prosthetic stentless valve function.

Stentless aortic valve replacement in elderly patients.

OBJECTIVE: Seven-year clinical and hemodynamic results of the Cryolife O'Brien (CLOB) stentless bioprosthesis in elderly patients are reported. METHODS: From 1993 to 2000, 36 patients aged >75 years had a CLOB implanted in the aortic position. Eighteen (50%) were male. All patients were monitored with serial echocardiograms performed preoperatively, at discharge, six months, one year and yearly thereafter. RESULTS: The 30-day mortality was 2.4% (1/36). Actuarial survival at one, five and seven years were 96.7+/-1.5, 94.8+/-2.0 and 94.8+/-2.0%, respectively. Peak and mean gradients (PG and MG) reduced and effective orifice area index (EOAI) increased over time (P<0.001). Left ventricular mass index (LVMI) reduced by 32 g/m2 at discharge (P<0.001) and by 33 g/m2 at six months (P<0.001) without further significant changes. CONCLUSIONS: In our series CLOB xenograft resulted to be a satisfactory valve substitute in elderly patients.

Left ventricular mass regression after aortic valve replacement with CryoLife-O'Brien stentless aortic bioprosthesis.

BACKGROUND AND AIM OF THE STUDY: Left ventricular (LV) hypertrophy has been shown adversely to affect LV function and late outcome after aortic valve replacement (AVR). The study aim was to assess the time course of LV mass regression (LVMR) after AVR with a CryoLife-O'Brien stentless bioprosthesis, and to identify factors affecting late reduction of myocardial hypertrophy. METHODS: In total, 113 patients (60 males, 73 females; mean age 70.9+/-6.5 years) were studied by echocardiography preoperatively, at discharge, at six and 12 months postoperatively, and yearly thereafter. LV diameter and thickness were measured using M-mode echocardiography; LV mass was calculated using the Devereux formula and indexed by body surface area (BSA). RESULTS: LV end-systolic diameter, end-diastolic diameter, septal thickness and wall thickness decreased significantly after surgery (p <0.001). LV mass index (LVMI) was reduced by 16.6, 13.6, 10.1, 3.1, 3.3, 1.7, 2.6, and 1.8% at discharge and at 6 months and 1, 2, 3, 4, 5, and 6 years, respectively. Most LVMR occurred within the first year, with further (not significant) reductions at later examinations. Male sex (p = 0.002), arterial blood pressure > or =150 mmHg (p <0.001), LV ejection fraction (LVEF) < or =35% (p = 0.01), NYHA functional class > or = III (p = 0.01), atrial fibrillation (p <0.001), mean transvalvular gradient > or =40 mmHg (p = 0.001), and prevalent aortic incompetence (p <0.001) were factors influencing LVMR, independently of baseline effective orifice area and prosthesis size. CONCLUSION: AVR with the CryoLife-O'Brien stentless prosthesis resulted in significant LVMR. These findings encourage the use of this bioprosthesis in appropriate patients.

Time course of left ventricular remodeling after stentless aortic valve replacement.

BACKGROUND: Stentless aortic valves are associated with a significant decrease in left ventricular hypertrophy. This study examined the time course and factors affecting left ventricular mass regression (LVMR) after aortic valve replacement (AVR) with Cryolife O'Brien (CLOB) (Cryolife International, Atlanta, Ga) stentless valves. METHODS: Between 1993 and 2000, 130 consecutive patients underwent AVR with CLOB. Mean age was 71.3 +/- 6.3 years. Sixty-four (49.2%) were male. Mean body surface area (BSA) was 1.7 +/- 0.2 m(2). Mean valve size implanted was 23.6 +/- 2.0 mm. All patients were monitored with serial echocardiograms; the first study was performed preoperatively, and subsequent controls were at 6 months, 1, 2, 3, 4, 5, 6, and 7 years, respectively. Left ventricular mass was calculated by the Devereux formula and indexed by BSA. RESULTS: Analysis of variance showed a significant reduction in the left ventricular mass index (LVMI) over time (P < .001). Most LVMRs occurred within the first 6 months, and after 1 year LVMI had decreased by 37.5% with further, but not statistically significant, reductions at later examinations. We found that baseline BSA > 1.75 m(2), male sex, arterial blood pressure > or = 150 mm Hg, left ventricular ejection fraction < or = 35%, New York Heart Association functional class > or = III, non-sinus rhythm, and prevalent aortic incompetence to be factors influencing LVMR. LVMR was not related to postoperative effective orifice area < or = 0.85 cm/m(2) and prosthetic size. CONCLUSIONS: AVR with a CLOB valve is followed by a significant LVMR that occurs soon after surgery. It is influenced by several patient-related factors: most of them can be predicted preoperatively.

Coronary artery bypass grafting in patients with dialysis-dependent renal failure: ten-year results.

BACKGROUND: Coronary artery disease has been reported to be accelerated in patients with chronic renal failure on maintenance dialysis. Coronary artery bypass grafting (CABG) in patients on long-term dialysis is still a debated issue. METHODS: We retrospectively reviewed 19 patients (12 men, 7 women, mean age 64 +/- 11.2 years) with end-stage renal disease who underwent CABG between 1990 and 2000. Operative procedures were CABG alone in 15 (78.9%) patients and CABG associated with valve procedures in 4 (21.1%) patients. RESULTS: The early (30-day) mortality rate was 10.5% (2 of 19 patients). Non-fatal complications occurred in 6 patients (31.5%). Four delayed deaths occurred; the actuarial survivals at 1, 2, 5 and 10 years were 0.86 +/- 0.14, 0.78 +/- 0.10, 0.68 +/- 0.13 and 0.54 +/- 0.15 respectively. Among 13 survivors the mean Canadian Cardiovascular Society class was 1.3 +/- 0.3 (p < 0.001 vs preoperatively). ANOVA procedures showed age (p = 0.01), Canadian Cardiovascular Society class > or = III (p < 0.001), urgent/emergency operation (p < 0.001), left ventricular ejection fraction < 0.50 (p < 0.001), a prior myocardial infarction (p = 0.01), a preoperative mean creatinine level > or = 5 mg/dl (p = 0.02) and a duration of dialysis > or = 60 months (p = 0.03) to be strongly related to early and delayed mortality. CONCLUSIONS: CABG in patients with dialysis-dependent chronic renal failure is associated with acceptable results. Accurate patient selection, early referral to surgery, and adequate perioperative management are advisable.

Early and midterm results of model 300 CryoLife O'Brien stentless porcine aortic bioprosthesis.

BACKGROUND: The Cryolife O'Brien (CLOB) is a composite stentless bioprosthesis constructed from noncoronary leaflets of three porcine aortic valves. This study aimed to investigate early and midterm results after aortic valve replacement with CLOB xenograft. METHODS: Between 1993 and 2000, the CLOB was implanted in 125 patients (62 men; mean age 71.3+/-6.4 years). Mean prosthesis size was 23.6+/-2 mm. Mean follow-up time was 37.0+/-12.1 months. Patients underwent echocardiographic studies preoperatively, at discharge, at 6 and 12 months postoperatively, and yearly thereafter. RESULTS: Early (30-day) mortality rate was 2.4% (3 of 125 patients). Of the four late deaths, none was valve related. Actuarial 7-year survival was 93.6%+/-3%. Seven-year freedom from primary valve failure was 98.1%+/-1.8%. All patients showed an improvement of functional status (p < 0.001). ANOVA revealed a significant reduction over time in peak and mean systolic gradients (p < 0.001). Effective orifice area index increased (p < 0.001) and left ventricular mass index significantly reduced in all valve sizes (p < 0.001) during this time interval. CONCLUSIONS: Because the early and midterm results with CLOB xenograft have been satisfactory, we encourage its use as a valve substitute, particularly in patients with small aortic roots.

Aortic repair in Marfan's syndrome: prevention of mechanical leaflets damage.

Aortic incompetence in Marfan's syndrome results from distortion or dilatation of the sinuses of Valsalva, annuloaortic ectasia or a combination of these problems. Valve leaflets in these patients are macroscopically normal in spite of aortic insufficiency. Replacement of the ascending aorta, root and aortic valve with a composite graft was, for a long time, the treatment of choice for Marfan patients. Valve-preserving procedures (remodeling or reimplantation) provide the advantages of avoiding the shortcomings of standard surgical techniques, and maintaining the functional integrity of the left ventricular (LV) outflow tract, aortic root and ascending aorta. We developed a modified valve-sparing reimplantation technique for avoiding leaflet damage. This was achieved by leaving a 'cushion' of aortic wall (8--10 mm) that, sewn on the Dacron graft, works as a 'damper' and prevents leaflets injury during the systolic opening of the valve. For final judgment of this operative method long-term results are necessary.

The CryoLife O'Brien stentless porcine aortic bioprosthesis: 5-year follow-up.

BACKGROUND: Mortality, morbidity, complication rates, and echo hemodynamic results using the Cryolife O'Brien stentless aortic bioprosthesis over a 5-year period are reported. METHODS: The stentless valve was implanted in 97 conscecutive patients, 54 male and 43 female, mean age 70.9 +/- 6.5 years. All patients underwent preoperative, discharge (early study), 6-month (intermediate study), and late (18.3 +/- 10.4 months) echocardiography. RESULTS: The actuarial 5-year survival rate was 93.9% +/- 3%. Aortic regurgitation was absent in 95.5%, mild in 3.4%, and moderate in 1.1%. Peak and mean systolic gradients were significantly lower at discharge (p < 0.001) and at the 6-month follow-up (p < 0.001) but did not significantly fall further at the late study (p = NS). The effective orifice area index at discharge (p < 0.001) and at 6 months (p < 0.001) differed significantly from preoperative values, but variations at late study were not significant (p = NS). Left ventricular mass index decreased early postoperatively (p < 0.001) and at 6-month assessment (p < 0.001) with a further significant reduction at late echocardiography (p = 0.04). CONCLUSIONS: The 5-year results of this stentless valve showed a low rate of valve-related complications with excellent hemodynamic performance in all valve sizes.

Early recovery of left ventricular function after stentless versus stented aortic valve replacement for pure aortic stenosis and severe cardiac dysfunction.

OBJECTIVE: The aim of this study was to evaluate early recovery of systolic function after stentless aortic valve replacement (AVR) versus stented AVR. METHODS: Fifty-four consecutive patients with pure aortic stenosis and impaired left ventricular function (LVEF < or = 35%) were studied retrospectively. Aortic regurgitation, concomitant valvular or coronary artery surgery, atrial fibrillation, and a previous AVR were exclusion criteria. Twenty-two patients (mean age, 70.0 +/- 6.5 years) received a stentless bioprosthesis and 32 (mean age, 58.9 +/- 6.2 years, P =.031 between groups) a mechanical or stented biologic valve. Patients underwent echocardiography preoperatively, at discharge, at 6 months, and at 1 year after surgery. RESULTS: At 6 months, analysis of variance demonstrated significant differences between groups in fractional shortening measured at the endocardium and midwall fractional shortening (<0.001), velocity of circumferential shortening (P <.001) ejection fraction (P =.02), left ventricular mass index (P <.001), systolic meridional wall stress, and circumferential wall stress (P <.001), One-year studies confirmed these findings. CONCLUSION: LV function showed, after a stentless AVR, an early recovery greater than in patients receiving a stented valve.

Clinical and hemodynamic evaluation of 21 mm and 23 mm Cryolife-O'Brien stentless bioprostheses implanted in the aortic position.

BACKGROUND: The aim of this study was to investigate early and mid-term results after aortic valve replacement with Cryolife-O'Brien stentless bioprosthesis, model 300. METHODS: Records of 59 patients who received a 21 or 23 mm (Group A) aortic Cryolife-O'Brien stentless valve were retrospectively reviewed and compared to 54 patients who received a valve > or = 25 mm (Group B). Group A patients were mainly female (p < 0.001), were older (p = 0.034), had dominant aortic stenosis (p = 0.011), and a smaller (p < 0.001) body surface area. Effective orifice area index was larger (p = 0.041) and left ventricular mass index higher (p = 0.024) in Group B. RESULTS: The actuarial survival at 5.5 years was 94.9 +/- 2.3% and 92.5 +/- 4.3% in Group A and B respectively (p = NS). The actuarial freedom from all events was 85.1 +/- 6.1% and 88.2 +/- 5.2% in Group A vs Group B respectively (p = NS). At late echocardiographic studies performed between 4 and 42 months (mean 27.3 +/- 6.1 months) postoperatively, peak and mean gradients decreased and effective orifice area index increased over the follow-up period (p = NS between groups). Left ventricular mass index decreased by 25% (p < 0.001) in Group A and by 20% (p < 0.001) in Group B from preoperatively and a further 13% (p = 0.034) and 8.5% (p = 0.004), respectively, from the early to the late study. No significant difference in left ventricular mass regression was noticed between groups (p = NS). CONCLUSIONS: The Cryolife-O'Brien porcine stentless bioprosthesis showed satisfactory mid-term results and may represent a good choice for patients with a small aortic annulus selected for a biological valve.

A right atrial approach in redo postinfarction ventricular septal defect.

Despite improvements in surgical techniques, post-infarction ventricular septal defect remains a surgical challenge that is associated with significant early and late mortality. Furthermore, the recurrence of the defect after primary correction occurs in approximately 10-25% of patients, and the operative risk increases because of a difficult dissection that is often complicated by previous patent grafts. The repair of recurrent ventricular septal defect has generally been performed by ventriculotomy in the infarcted zone. The authors propose an alternative approach that, when the rupture is posterior, allows its complete visualization, and avoids any further ventriculotomy in an already impaired ventricle.

Multicenter study of stentless valve replacement in the small aortic root.

OBJECTIVE: A clinical study was conducted to evaluate the results of stentless porcine valves in patients with a small aortic root (19- and 21-mm aortic anulus). METHODS: Of 567 patients, from 4 surgical institutions, 171 patients (30.1%) had a small aortic root, comprising 163 cases with calcified aortic stenosis and 8 cases with predominant valvular insufficiency. Sixty patients had associated mitral or coronary lesions. Mean age was 72 +/- 4.2 years. Forty-seven patients with a small aortic root had a 19-mm anulus, and 124 patients had a 21-mm anulus. The body surface area was, respectively, 1.55 +/- 0.2 m2 and 1.78 +/- 0.45 m2. Hemodynamic evaluation of the stentless valve comprised serial measures of mean gradients, effective orifice area, and left ventricular mass reduction. Complication rates for secondary events were evaluated over a 6-year period. RESULTS: The hospital mortality rate was 3.5%. The mean gradients after the first year were 9 +/- 2 mm Hg and 6 +/- 1.7 mm Hg in patients with a 19-mm and a 21-mm anulus, respectively. Effective orifice area was 1.45 +/- 0.3 cm2 and 1.72 +/- 0.4 cm2. Gradients and surfaces remained stable throughout the study period. Aortic regurgitation was zero to trace. Left ventricular mass at discharge and at 1 year were, respectively, 296 +/- 127 g and 215 +/- 102 g for patients with a 19-mm anulus and 281 +/- 75 g and 236 +/- 15 g for patients with a 21-mm anulus. CONCLUSIONS: Stentless valves are a suitable device for elderly patients with small aortic roots, which leave only mild residual obstruction.

[The Tirone Davis operation in a young patient with Marfan syndrome. Description of a clinical case]. / Intervento di Tirone David in giovane paziente affetta da sindrome di Marfan. Descrizione di un caso clinico.

We report a case of a young woman affected with Marfan's syndrome, with an ascending aortic aneurysm and mild aortic insufficiency, who underwent a valve-sparing operation as described by Tirone David. In many patients with Marfan's syndrome, aortic valve dysfunction is caused by dilatation of the sinotubular junction with distortion of the sinuses of Valsalva, and often with intact aortic valve leaflets. In these patients, if the aortic valve leaflets are normal at echocardiography, a more aggressive approach may be advisable in order to prevent irreversible damage to the aortic valve leaflets. We believe that surgery is indicated when the aortic root increases rapidly, even if it does not reach a diameter of 50 mm, which represents the current indication for asymptomatic patients with ascending aortic aneurysm. This makes it possible to perform a valve-sparing operation instead of the composite replacement of the aortic valve and ascending aorta, which is still considered the standard treatment for these patients. The procedure described here represents an attractive choice for managing aortic root dilatation and annuloaortic ectasia in Marfan patients, with the benefit of avoiding all the well-known complications involved in prosthetic aortic valves.

[The recurrence of a postinfarct interventricular defect. An alternative approach]. / Recidiva di difetto interventricolare postinfartuale. Un approccio alternativo.

Despite improvement of surgical techniques and perioperative management, the postinfarction ventricular septal defect still remains a surgical challenge associated with a significant early and late mortality. Furthermore, the recurrence of the defect after primary correction occurs in about 10-25% of patients and the operative risk increases because of difficult dissection that is often complicated by previous patent grafts. Repair of recurrent posterior postinfarction ventricular septal defect has generally been performed by ventriculotomy in the infarcted zone. This approach carries a significant mortality and morbidity from hemorrhage or further compromise of ventricular function. We propose an alternative approach to a recurrent defect that, when the rupture is posterior, makes it possible to achieve its complete visualization, avoiding any further ventriculotomy in an already impaired ventricle. This transatrial approach seems to be a safe technique. Moreover, the simplicity of this operation and the patient's rapid recovery contrasts remarkably with the transventricular approach used in previous patients. Nevertheless, care must be taken to avoid damage to the tricuspid valve.

[Transesophageal and epicardial echocardiography in the evaluation of conservative surgery of the mitral valve. Complementary methods?]. / L'ecocardiografia transesofagea ed epicardica nella valutazione della chirurgia conservativa della valvola mitrale. Metodiche complementari?

BACKGROUND: Over the last two decades several new surgical methods for repairing a regurgitant mitral valve have been proposed. Unfortunately, early applications of such techniques were not always encouraging because the evaluation in the operating room led to false optimism due to a marked difference between static and functional anatomy of the repaired valve. By means of intraoperative echocardiography, be it transesophageal or epicardial, it is now possible to assess the functional result immediately after valvuloplasty and to decide about further surgery, right at the operating table. MATERIALS AND METHODS: Thirty-six patients (mean age 61.8 years) who underwent mitral valve repair were studied; all underwent preoperative transthoracic echocardiography in the week preceding surgery, and intraoperative transesophageal echo before cardiopulmonary bypass. The surgical results were evaluated by epicardial and/or transesophageal echocardiography in the operating room, and by transthoracic and/or transesophageal approach during follow-up. RESULTS: In 5 patients with intraoperative echocardiography done before valve repair, leaflets pathology and subvalvular apparatus were better evaluated. Besides, in 3 patients the more evident calcification of the leaflets led the surgeon to decide on direct replacement rather the reconstruction of the valve. The postoperative assessment has shown an unsatisfactory correction in 8 patients (24%). In 4 of these patients an important mitral regurgitation was reported and in 2 there was a moderate regurgitation. In the last 2, a iatrogenic stenosis had resulted. Of these 8 patients, 6 underwent valve replacement using an artificial valve. The other 2 patients (one with moderate stenosis and the other with moderate regurgitation) did not undergo a second operation because of the excessive operating time taken for valvuloplasty and the advanced age of the patients. During follow-up, from 6 to 54 months, a remarkable mitral regurgitation was present in 4 patients, one being severe and the other moderate. A persistence of ventricular dilatation was present only in these patients, while in the remainder the left ventricular diameters were normal. Finally, the mitral valve area after six months was between 1.5 an d4 cm2. CONCLUSIONS: Intraoperative echocardiography, both transesophageal and epicardial, can help the surgeon by giving him useful diagnostic information, if carried out before reconstructing the mitral valve with regurgitation. Its application is even more useful if applied straight after the surgical intervention. Unsatisfactory results may be evidenced at once and the operating team will decide right at the table for further repair or replacement, thus avoiding a second operation and the relevant risks.

[The usefulness of transesophageal echocardiography in the follow-up of patients operated on for replacement of the ascending aorta with a tubular-valvular prosthesis (Cabrol's intervention)]. / Utilità dell'ecocardiografia transesofagea nel follow-up dei pazienti operati di sostituzione dell'aorta ascendente con protesi tubulo-valvolata (intervento di Cabrol).

OBJECTIVES: The usefulness of transesophageal echocardiography (TEE) in assessing the postoperative results of aortic root replacement (Cabrol's procedure) was evaluated. METHODS: Between 1986 and 1993, 31 patients underwent replacement of the aortic valve and ascending aorta by a composite graft using the Cabrol procedure. Twenty-six patients had annuloaortic ectasia, two type I DeBakey dissection and four type II dissection. Hospital mortality was 9.7%. Studies were performed in 18 patients, two to 70 months (mean 27.5 months) after composite graft replacement. The following features were examined: prosthetic aortic valve function, coronary graft morphology and function, tubular graft and aneurysm wrapped around morphology and dimensions, presence of intimal flap, false lumen and thrombus in the false lumen and persistence of right atrial fistula. RESULTS: Periprosthetic leakage with significant regurgitation was detected by TEE in 3 (16.6%) of 18 patients. In one patient with infected aortic graft a fistula between the periprosthetic space and the right ventricle was detected (confirmed at reoperation). In another patient occlusion of the graft for left coronary artery was noted. In three patients (16.6%) an aneurysm of the periprosthetic space with perivalvular leakage and persistence of the fistula with the right atrium was visualized. In the two patients operated for DeBakey type I dissection an intimal flap persisted distal to the graft and in one patient flow was detected in the false lumen, while it was totally obliterated in the other. CONCLUSIONS: 1) Complications after Cabrol's procedure are not infrequent; although the real importance of some of them (periprosthetic aneurysm, persistence of dissection) is uncertain, a careful follow-up may be essential to improve the long term survival. 2) TEE is a useful and well-tolerated procedure for postoperative follow-up of patients who underwent aortic root replacement with Cabrol's procedure.