Henryk Siniawski

Long-Term Results in Patients With Idiopathic Dilated Cardiomyopathy After Weaning From Left Ventricular Assist Devices

Background—Since our first successful left ventricular assist device (LVAD) explantation in a patient with idiopathic dilated cardiomyopathy (IDCM) in 1995, an additional 31 IDCM patients have been weaned in our department. Echocardiographic evaluations during repeated “off-pump” trials were the cornerstone for weaning decisions. After 9 years of experience, we assessed the reliability of our weaning criteria in light of the long-term results. Methods and Results—We evaluated all of the IDCM patients who were weaned between March 1995 and March 2004 with regard to preservation of cardiac function without LVAD support and survival after weaning. Additionally, we reviewed our echocardiographic data to assess their predictive value for long-term stability of cardiac function after weaning. The 32 weaned IDCM patients showed a survival rate of 78.3%±8.1 at 5 years after LVAD explantation. Heart failure (HF) recurred during the first 3 years after weaning in 31.3%. Only 2 patients died because of HF after weaning; the other patients with HF recurrence were successfully transplanted. Off-pump LV end-diastolic diameter >55 mm and/or LVEF <45% before LVAD removal, as well as history of HF ≥5 years before LVAD implantation, appeared to be major risk factors for early recurrence of HF. Patients without any of these 3 risk factors showed no HF recurrence during the first 3 years after weaning, but at the same time, all of those with at least 2 of these 3 risk factors developed early recurrence of HF. In patients with HF recurrence during the first 3 postweaning years, a significant LVEF decrease already occurred during the first month after weaning, whereas in those with long-term stable cardiac function even at the end of the sixth postweaning month, the LVEF was not different from that before LVAD removal. Conclusions—For selected patients with IDCM, weaning from LVADs is a clinical option with good results over >9 years and should, therefore, be considered in those with cardiac recovery after LVAD implantation. Off-pump echocardiographic data are reliable for the detection of LV recovery and prediction of long-term cardiac stability after weaning.

Prediction of Cardiac Stability After Weaning From Left Ventricular Assist Devices in Patients With Idiopathic Dilated Cardiomyopathy

Background— During ventricular assist device (VAD) unloading, cardiac recovery is possible even in patients with chronic heart failure (HF). We sought parameters predictive of cardiac stability after VAD removal. Methods and Results— Among 81 patients weaned since March 1995, a homogenous group of 35 with idiopathic dilated cardiomyopathy weaned from left VADs was selected. We evaluated echo data obtained before left VAD implantation and during “off-pump” trials before explantation, histological changes, and serum anti-&bgr;1-adrenoceptor-autoantibody disappearance during unloading, duration of unloading, and HF duration. Postweaning 10-year survival with native hearts reached 70.7±9.2%. During the first 5 years, HF recurred in 13 patients (37.1%). Only 6 (17.1%) died after HF recurrence or noncardiac complications related to left VAD explantation. Comparison of patients with and without long-term cardiac stability showed that stable patients were younger, HF history and recovery time during unloading shorter, and preweaning left ventricular assessment revealed higher left ventricular ejection fraction, lower short/long axis ratios, and higher end diastolic relative wall thicknesses. For left ventricular ejection fraction ≥45% at end diastolic diameter of ≤55 mm, predictive value for ≥5-year cardiac stability was 87.5%. Left ventricular ejection fraction time course during the first 6 postweaning months appeared predictive for long-term stability. HF history >5 years and preweaning instability of cardiac improvement appeared predictive for HF recurrence. Conclusions— In idiopathic dilated cardiomyopathy, left VAD removal can be successful for >12 years even with incomplete cardiac recovery. Pre-explantation left ventricular ejection fraction, left ventricular end diastolic diameter and relative wall thicknesses, stability of unloading-induced cardiac recovery, duration of left VAD support, and HF duration before left VAD insertion allow identification of patients able to remain stable for >5 years. Time course of left ventricular ejection fraction during the first 6 postweaning months allows prognostic assessment.

Morphometric analysis of aortic media in patients with bicuspid and tricuspid aortic valve.

BACKGROUND Patients with bicuspid aortic valves tend to develop dilatation of the ascending aorta. The aim of this study was to analyze whether or not there is any histologic difference in the aortic media of patients with a bicuspid aortic valve or a tricuspid aortic valve. METHODS A morphometric analysis of the wall of the ascending aorta was performed in 107 patients with bicuspid aortic valves undergoing aortic valve operations. The thickness of the elastic lamellae of the aortic media and the distances between the elastic lamellae were measured with the use of an image analysis system. The histologic specimens of the ascending aorta from 61 surgical patients with tricuspid aortic valve disease served as a control. RESULTS The patients with bicuspid aortic valves had thinner elastic lamellae of the aortic media (2.71 +/- 0.23 microm) of the ascending aortic wall than the patients with tricuspid aortic valve disease (2.83 +/- 0.23 microm) (p = 0.006). The patients with bicuspid aortic valves also had greater distances between the elastic lamellae (27.21 +/- 8.69 microm) of the ascending aortic wall in comparison with the patients with tricuspid aortic valve disease (24.34 +/- 5.32 microm) (p = 0.033). There was no difference in the total thickness of the aortic media between the groups (p = 0.62). CONCLUSIONS Patients with a bicuspid aortic valve had thinner elastic lamellae of the aortic media and greater distances between the elastic lamellae than patients with a tricuspid aortic valve.

Heart failure reversal by ventricular unloading in patients with chronic cardiomyopathy: criteria for weaning from ventricular assist devices

Aims Unloading-promoted reversal of heart failure (HF) allows long-term transplant-free outcome after ventricular assist device (VAD) removal. However, because few patients with chronic cardiomyopathy (CCM) were weaned from VADs (the majority only recently), the reliability of criteria used for weaning decisions to predict long-term post-weaning success is barely known. After 15 years of weaning experience, we assessed this issue. Methods and results In 47 patients with CCM as the underlying cause for HF, who were part of a total of 90 patients weaned from bridge-to-transplant-designed VADs since 1995, we analysed data on cardiac morphology and function collected before VAD implantation, echocardiographic parameters recorded during ‘off-pump’ trials, duration of HF before implantation, and stability of recovery before and early after VAD removal. Post-weaning 5 year freedom from HF recurrence reached 66%. Only five patients (10.6%) died due to HF recurrence or weaning-related complications. Pre-explantation off-pump left ventricular ejection fraction (LVEF) of ≥50 and ≥45% revealed predictive values for cardiac stability lasting ≥5 years after VAD removal of 91.7 and 79.1%, respectively. With each unit of LVEF reduction, the risk of HF recurrence became 1.5 times higher. The predictive value of LVEF ≥45% also became >90% if additional parameters like pre-explantation LV size and geometry, stability of unloading-induced cardiac improvement before VAD removal, and HF duration before VAD implantation were also considered. Definite cut-off values for certain parameters (including tissue-Doppler-derived LV wall motion velocity) allowed formulation of weaning criteria with high predictability for post-weaning stability, also in patients with incomplete cardiac recovery. Conclusions Ventricular assist device removal in CCM patients is feasible and can be successful even after incomplete cardiac recovery. Parameters of pre-explantation cardiac function, LV size and geometry, their stability during final off-pump trials, and HF duration allow detection of patients with the potential to remain stable for >5 post-weaning years.

Aortic valve replacement with the Mitroflow pericardial bioprosthesis: Durability results up to 21 years

OBJECTIVE The study aim was to analyze the performance profile of a large series of Mitroflow pericardial valves (Sorin Group Canada Inc. Mitroflow Division) in the very long term. METHODS Data from 1513 patients with isolated aortic valve replacement who received pericardial bioprostheses between 1986 and 2007 were analyzed. Cumulative duration of follow-up was 6164 patient-years with a maximum duration of 21 years. Actuarial rates of valve-related events were calculated by the Kaplan-Meier method and the Cox multivariate analysis to identify independent determinants of outcome. RESULTS Hospital mortality for elective surgery was 2.5%. Late death was 40.6%. Reoperation was required in 86 (5.7%) patients and was valve related in 83: structural valve deterioration in 64 (4.2%) patients, prosthetic valve endocarditis in 17 patients (1.1%), valve thrombosis in 1, and periprosthetic leak in 1. Rates of 20-year actuarial freedom from valve-related morbidity were as follows: structural valve deterioration 84.8% (actual 96.6%) in patients 70 years of age or older; thromboembolism 94.1%; and prosthetic valve endocarditis 96.8%. Twenty-year actual risk of reoperation for structural valve deterioration was 11.4% in all patients and 3.4%, in patients 70 years or age or older. Advanced age, renal insufficiency, pulmonary disease, and low body mass index were independent risk factors for late outcome (P < .001). CONCLUSIONS After 2 decades of follow-up, the Mitroflow pericardial aortic valve continues to be a valve of choice with a predictable low rate of valve-related events, particularly for patients over the age of 65 to 70 years and others with comorbidities.

Homograft aortic root replacement in native or prosthetic active infective endocarditis: Twenty-year single-center experience

OBJECTIVE We compared early and long-term results of cryopreserved homograft aortic root replacement in native valve endocarditis or prosthetic valve endocarditis associated with periannular abscess. METHODS Between May 1986 and December 2007, 1163 patients with endocarditis were operated upon. Of these, 221 patients (n = 185 men, median age 55 years) had homograft aortic root replacement due to 99 cases of native valve endocarditis (45%) and 122 of prosthetic valve endocarditis (55%). Perinannular abscess developed in 189 patients (86%), and aortoventricular dehiscence in 120 (63.5%) of them. Perioperative characteristics, probability of survival, freedom from recurrence, and reoperation were analyzed. Follow-up (mean 5.2 +/- 0.4 years, maximum 18.4 years) was completed in 96.8% with a total of 1127 patient-years. RESULTS Overall native valve endocarditis survival at 30 days and 1, 5, and 10 years was 83.8% +/- 3.7%, 76.6% +/- 4.3%, 66.5% +/- 4.9%, and 47.3% +/- 5.6%, respectively, significantly better than for patients with prosthetic valve endocarditis, who had a greater tendency toward abscess formation (P = .029). Thirty-one patients (14.0%) required reoperation either for structural valve deterioration (n = 19, 8.6%), with a greater tendency in patients aged <40 years, or for recurrent endocarditis of the homograft (n = 12, 5.4%). One-year reoperation mortality rate was 16.1% (n = 5). CONCLUSIONS Homograft aortic root replacement in active infective endocarditis with periannular abscess formation shows satisfactory early and long-term results with significantly better survival in native valve endocarditis than prosthetic valve endocarditis. It is associated with a low recurrence rate, although the risk of structural valve deterioration increases over time, especially in young patients, and reoperation remains a challenge. In our institution, the homograft remains the preferred valve substitute in active infective endocarditis with periannular abscess formation.

Reduction aortoplasty for dilatation of the ascending aorta in patients with bicuspid aortic valve

BACKGROUND Individuals with bicuspid aortic valve tend to develop a dilatation of the ascending aorta. It is controversial whether the dilated ascending aorta should be replaced with a tube graft or whether the diameter of the aorta should be reduced by reduction aortoplasty. Furthermore, it is unclear whether an external prosthetic support of the reduction aortoplasty is necessary. The aim of this study is to analyze the results of reduction aortoplasty with and without external prosthetic support. METHODS Between 1985 and 1999, a total of 115 patients with bicuspid aortic valve and dilatation of the ascending aorta underwent reduction aortoplasty in combination with other types of open-heart procedure at our institution. The diameter of the ascending aorta was measured before and early after surgery and then later between 12 and 144 months (mean 40 months) postoperatively using echocardiography and computed tomography. RESULTS The reduction aortoplasty decreased the internal diameter of the aorta from 48.7+/-5.1 mm preoperatively to 36.9+/-3.6 mm early after surgery (p = 0.0001). During follow-up, there was no increase of the aortic diameter either in patients with external prosthetic support or in 97 of 106 patients without external prosthetic support. The diameter increased only in 9 (8.5%) of 106 patients without external aortic support by 4 to 8 mm. In patients with postoperative diameter increase, the aortic diameter after operation had been higher than in patients without a postoperative increase of the aortic diameter (41.4+/-3.1 mm vs 36.6+/-3.4 mm; p < 0.0001). CONCLUSIONS Reduction aortoplasty showed good long-term results in patients with bicuspid aortic valve and dilatation of the ascending aorta. Redilation of the aorta occurred only in patients with a suboptimal diameter reduction.

Decreased plasma concentration of brain natriuretic peptide as a potential indicator of cardiac recovery in patients supported by mechanical circulatory assist systems

OBJECTIVES We sought to investigate the relationship between the plasma concentration of brain natriuretic peptide (BNP), echocardiographic findings and the clinical outcome of patients supported with ventricular assist devices (VADs) to determine the role of BNP as a predictor for cardiac recovery. BACKGROUND Ventricular unloading in patients with end-stage heart failure supported by VADs may lead to myocardial recovery. The BNP is produced in the myocardium in response to chronic volume overload, but the effects on it of ventricular unloading by VADs are largely unknown. METHODS Twenty-one patients diagnosed with nonischemic cardiomyopathy and supported by VADs were evaluated for echocardiographic data and blood chemistry including BNP. They were divided into patients who died while on mechanical support (group I; n = 9), patients who were transplanted (group II; n = 8) and patients who were successfully weaned off the system and did not require transplantation (group III; n = 4). RESULTS Brain natriuretic peptide plasma concentrations decreased significantly after initiation of mechanical circulatory support (p = 0.017). Furthermore, the changes in BNP plasma concentrations showed a faster decrease to normal levels within the first week after implantation of the VAD in patients who were weaned off the system (group III) compared to patients in group I and group II. CONCLUSIONS This study shows that ventricular unloading with VADs decreases BNP plasma concentrations in patients who suffer from end-stage heart failure. Furthermore, we hypothesize that an early decrease of BNP plasma concentration may be indicative of recovery of ventricular function during mechanical circulatory support.

Different hemodynamic stress of the ascending aorta wall in patients with bicuspid and tricuspid aortic valve.

Abstract  It is unclear whether ascending aorta dilation in patients with bicuspid aortic valve is caused by abnormal hemodynamics or by a common developmental defect of the aortic valve and aortic wall. We performed an echocardiographic study to examine the differences in hemodynamic stress at the ascending aorta in patients with bicuspid and tricuspid aortic valve. We studied prospectively 58 consecutive patients referred for preoperative echocardiographic examination with aortic valve stenosis and either bicuspid or tricuspid valve and an ascending aortic diameter of ≤4.5 cm. Echocardiographic examination was performed from the parasternal long‐axis view using ALOKA SDD 5.500 (Aloka, Tokyo) with 3.5 MHz probe. With aortic wall tissue Doppler imaging we obtained wall motion velocity patterns from the anterolateral and posteromedial region of the ascending aorta. The tissue Doppler examination showed a significantly higher peak systolic wall velocity of the anterolateral region of the ascending aorta in patients with bicuspid aortic valve (12.2 ± 4.3 cm/sec vs. 8.8 ± 2.6 cm/sec, p = 0.047). We conclude that in patients with bicuspid aortic valve and aortic valve stenosis the anterolateral region of the ascending aorta is subject to greater hemodynamic stress than in patients with tricuspid aortic valve.

Stentless aortic valves as an alternative to homografts for valve replacement in active infective endocarditis complicated by ring abscess

BACKGROUND The valve substitute of choice in active infective aortic valve endocarditis complicated by annulus abscess in our institution is the cryopreserved homograft. To avoid implantation of any prosthetic material, the Shelhigh No-React stentless valves and conduits may be considered an alternative when no suitable homograft is available. METHODS Between March 1986 and January 2001, 452 homografts were implanted in the aortic position. From January 2000 to August 2001, 75 Shelhigh No-React prostheses were implanted at our institution. In 25 consecutive patients (study group) with aortic annulus abscess, urgent aortic valve replacement with the Shelhigh SuperStentless and Stentless Aortic Valve Conduit was undertaken. Patients (16 male, 9 female; age, 49 +/- 19 years) were studied with follow-up until March 2002. The control group comprised 68 consecutive historical patients (46 male, 22 female; age, 53 +/- 14.4 years) with similar disease treated between January 1997 and December 1999 in whom an aortic homograft was implanted. This group was also followed up until March 2002. Demographic data and preoperative characteristics of the patients were without significant differences. Patients were studied by echocardiography. RESULTS Sixty-day mortality was 16% (11 patients) in the control group compared with 12% (3 patients) in the study group. Recurrent infection occurred in 4% in both groups. The instantaneous and mean Doppler gradients yielded no significant differences (19.4 +/- 10.4 mm Hg and 11.8 +/- 5.7 mm Hg versus 18.2 +/- 8.7 mm Hg and 10.9 +/- 5.3 mm Hg, respectively). The mean effective orifice area calculated from Doppler flow velocity for the stentless valve was 2.3 +/- 0.6 cm2. Preoperative evaluation of left ventricular dimensions and global left ventricular systolic function did not vary significantly between the two groups. However, postoperatively evaluated left ventricular end-diastolic diameter dimensions in the study group were significantly smaller than those in the control group (47.6 +/- 7.9 mm versus 56 +/- 9.5 mm; p = 0.05). Ejection fraction was similar in both groups (56.2% +/- 12.8% for the study [Shelhigh] and 52.6% +/- 16.8% for the control [homograft] group). CONCLUSIONS Our experience with both the Shelhigh No-React SuperStentless and Stentless Aortic Valve Conduit in patients with native or prosthetic aortic valve endocarditis appears to demonstrate good results, similar to those of cryopreserved homografts. Ease of implantation and favorable effective orifice area and pressure gradients, as well as the No-React anticalcification treatment, are promising factors.