Comparative Analysis: Implementation of a Pre-operative Educational Intervention to Decrease Anxiety Among Parents of Children With Congenital Heart Disease.

PURPOSE: The present study evaluated the efficacy of a nursing educational intervention in alleviating the level of parental anxiety in the parents of children who required heart surgery for the first time. DESIGN AND METHODS: A comparative study was used to explore the parents of children who had to undergo cardiac surgery. Parents of children were randomized into 2 groups: 1) control group and 2) experimental group or parents that received the educational intervention about PICU stay. RESULT: The results of STAY-1 showed that the average anxiety score of group 1 was lower than that of group 2 (63.0 [SD=3.5] vs. 70.4 [SD=2.8]). CONCLUSION: In order to decrease levels of parental anxiety and stress prior to paediatric surgery, parents should be adequately informed about planned therapeutic procedures. PRACTICE IMPLICATIONS: We speculate that pre-surgery parent education on what to expect before, during and after their child's cardiac surgery may improve parents' knowledge and satisfaction and decrease anxiety.

Comparison of Left Ventricular Myocardial Structure and Function in Patients with Aortic Stenosis and Those with Pure Aortic Regurgitation.

OBJECTIVE: We aimed to support the structural and functional distinction between aortic stenosis (AS) and aortic regurgitation (AR). METHODS: Biopsy specimens taken from 70 selected patients (35 with AS and 35 with AR) undergoing aortic valve replacement (AVR) were analyzed for their cardiomyocyte dimensions and structure, interstitial fibrosis and contractile function. To determine normal values of contractile function, 10 donor hearts were analyzed. RESULTS: Cardiomyocyte diameter was higher in AS than in AR (22.7 ± 2.2 vs. 13.2 ± 0.7 µm, p < 0.001). Length was higher in AR (121.2 ± 9.4 vs. 95.6 ± 3.7 µm, p < 0.001). Collagen volume fraction was increased in both AS and AR, but was lower in the AS specimens (7.7 ± 2.3 vs. 8.9 ± 2.3, p = 0.01). Myofibril density was reduced in AR (38 ± 4 vs. 48 ± 5%, p < 0.001). Cardiomyocyte diameter and length were closely linked to the relative left ventricular (LV) wall thickness (R2 = 0.85, p < 0.001 and R2 = 0.68, p = 0.003). The cardiomyocytes of AS patients had higher Fpassive (6.6 ± 0.3 vs. 4.6 ± 0.2 kN/m2, p < 0.001), but their total force was comparable. Fpassive was also significantly higher in AS patients with restrictive rather than pseudo-normal LV filling (7.3 ± 0.5 vs. 6.7 ± 0.6, p = 0.004). In AS patients, but not in AR patients, Fpassive showed a significant association with the cardiomyocyte diameter (R2 = 0.88, p < 0.001 vs. R2 = 0.31, p = 0.6). CONCLUSIONS: LV myocardial structure and function differ in AS and AR, allowing for compensative adjustment of the diastolic/systolic properties of the myocardium. © 2015 S. Karger AG, Basel.

Treatment of residual type A aortic dissection with implantation of the Djumbodis system: is purely endovascular treatment becoming a reality?

PURPOSE: To evaluate the usefulness of a new transfemoral device to avoid major complications related to residual type A aortic dissection following ascending aortic replacement. CASE REPORTS: Three men (aged 60, 61, and 72 years, respectively) with a residual type A aortic dissection following replacement of the ascending aorta 1, 4, and 5 years prior, respectively, were treated with the Djumbodis Dissection System. The residual dissection developed at the distal anastomosis of the aortic graft and involved all the aortic arch. The Djumbodis Dissection System is an uncovered steel stent, available in 3 lengths (40, 90, 140 mm), pre-mounted on a low pressure (0.3 bars) balloon catheter. The mesh of the device is sufficiently large to bring together the dissected layers without occluding main vital branches. The device was implanted through the femoral artery over a stiff guidewire to exclude the residual false lumen. Satisfactory aortic remodeling was documented in all cases at 1 year. CONCLUSION: The Djumbodis Dissection System might be a purely endovascular treatment to replace open surgery for residual type A aortic dissection. More cases and longer follow-up are required.

Epithelial-mesenchymal transition of epicardial mesothelium is a source of cardiac CD117-positive stem cells in adult human heart.

Epithelial-mesenchymal transition is implicated in the remodelling of tissues during development and in the adult life. In the heart, it gives origin to progenitors of fibroblasts, coronary endothelium, smooth muscle cells, and cardiomyocytes. Moreover, epicardially-derived cells determine myocardial wall thickness and Purkinje fibre network. Recently, the presence of numerous cardiac stem cells in the subepicardium of the adult human heart has been described and the hypothesis that epicardially-derived cells can contribute to the population of cardiac stem cells in the adult heart has been advanced. In an effort to test this hypothesis and establish a possible link between epicardium, epicardially-derived cells and cardiac stem cells in the adult human heart we have examined epicardial mesothelial cells in the normal and pathological adult human heart with ischemic cardiomyopathy in vivo and we have induced and documented their epithelial-mesenchymal transition in vitro. Noticeably, epicardial cells were missing from the surface of pathological hearts and the cells with the expression of epithelial and mesenchymal markers populated thick subepicardial space. When the fragments of epicardium from the normal hearts were cultured on the specific substrate formed by extracellular matrix derived from cardiac fibroblasts, we obtained the outgrowth of the epithelial sheet with the mRNA and protein expression characteristic of epicardium. TGFß induced cellular and molecular changes typical of epithelial-mesenchymal transition. Moreover, the epicardially-derived cells expressed CD117 antigen. Thus, this study provides evidence that cardiac stem cells can originate from epithelial-mesenchymal transition of the epicardial cells in the adult human heart.

Long-term enzyme replacement therapy for pompe disease with recombinant human alpha-glucosidase derived from chinese hamster ovary cells.

Pompe disease is a rare autosomal recessive myopathy due to the deficiency of lysosomal acid alpha-glucosidase. Clinical phenotypes range from the severe classic infantile form (hypotonia and hypertrophic cardiomyopathy), to milder late onset forms (skeletal myopathy and absence of significant heart involvement). Enzyme replacement therapy with recombinant human alpha-glucosidase derived from either rabbit milk or Chinese hamster ovary cells has been introduced and is undergoing clinical trials. Reported is a long-term follow-up of 3 Pompe patients presenting without cardiomyopathy, treated with recombinant human alpha-glucosidase derived from Chinese hamster ovary cells. This study suggests that enzyme replacement therapy can lead to significant motor and respiratory improvement in the subgroup of patients who start the therapy before extensive muscle damage has occurred. The recombinant enzyme derived from Chinese hamster ovary cells, administered at doses significantly higher than previously reported, appears to have the same safety as the drug derived from rabbit milk.

Severe prosthesis-patient mismatch after aortic valve replacement for aortic stenosis: Analysis of risk factors for early and long-term mortality.

BACKGROUND: Severe prosthesis-patient mismatch (PPM) is considered to further decrease survival compared to moderate PPM. This study aimed to assess the impact of severe PPM on survival after aortic valve replacement (AVR). METHODS: We retrospectively studied 2404 consecutive patients with PPM who underwent first-time AVR for pure stenosis between January 2003 and December 2014. Mismatch was moderate for indexed effective valve orifice >0.65 to <0.85cm2/m2 and severe for indexed effective valve orifice ≤0.65cm2/m2. Moderate mismatch occurred in 2165 patients (89%), and severe in 239 (11%) patients. Logistic multiple regression with bootstrapping and propensity score analyses were performed using 29 clinical and demographic data to assess the risk-adjusted impact of severe mismatch on mortality. The Cox proportional hazards model was constructed to process the long-term outcome. RESULTS: Early mortality was 2.3% (51/2165) in moderate mismatch group and 3.7% (9/239) in severe mismatch group (p=0.2). Mortality at 5 and 10 years, was 218/1470 (14.8%) and 252/585 (43.1%) for moderate mismatch and 43/198 (21.7%) and 61/105 (58.1%) for severe mismatch (p=0.02 and p=0.006). Multivariable predictors of late mortality were as follows: age ≥70 years, left ventricular ejection fraction ≤40%, indexed left ventricular mass >220g/m2 and concomitant coronary artery revascularization. After propensity score matching, conditional logistic regression analysis demonstrated no relationship between severe mismatch and increased mortality at 5 postoperative years (HR, 0.9; 95% CI, 0.7-1.6; p=0.06), whereas it was significant at 10 postoperative years (HR, 1.9; 95% CI, 1.2-2.5; p=0.03). During the follow-up, severe mismatch was associated with more frequent hospital readmissions for cardiac events (0.12 vs. 0.08 events/patient/year, p=0.007). CONCLUSIONS: Patients with severe mismatch had lower long-term survival and higher incidence of hospital readmissions for cardiac events. However, the effect of severe mismatch on outcome appeared mainly related to the preoperative risk profile of each patient.

Transcatheter palliation of congenital heart disease with reduced pulmonary blood flow.

BACKGROUND: Although surgical shunt is still considered as the best palliation of congenital heart disease with reduced pulmonary blood flow, stent implantation may be technically simpler, safer and more cost-effective than surgery in high-risk patients. This study evaluated the feasibility and results of this option in patients with duct-dependent pulmonary blood flow or systemic-to-pulmonary shunt malfunction. METHODS: Between April 2003 and July 2004, 9 patients (age 11 days-52 years, weight 2.1-52 kg) with complex congenital heart disease underwent stent implantation inside the patent ductus arteriosus (4 patients) or a stenotic surgical shunt (5 patients). RESULTS: The stenting procedure was successfully completed in all cases. The procedural time was 162 +/- 36 min (range 90-225 min). The fluoroscopy time was 33.8 +/- 6.8 min. No patient died. The morbidity rate was 22.2% (1 patient had local infection at the site of puncture and 1 had transient femoral artery pulse loss). After the procedure, the ductus/shunt diameter increased from 1.2 +/- 0.6 to 3.6 +/- 0.6 mm (p < 0.0001) and oxygen saturation improved from 74.0 +/- 6.5 to 85.2 +/- 3.3% (p < 0.01). Three patients underwent corrective surgery without technical problems after 8.0 +/- 1.0 months while oxygen saturation remained constantly >80% in patients still waiting for surgical repair (follow-up 5.3 +/- 3.1 months). CONCLUSIONS: Stent implantation is a technically feasible, safe and effective palliative option in high-risk surgical patients with congenital heart disease and reduced pulmonary blood flow. Although larger series are required to define the cost-effective clinical impact of this therapeutic option, it is reasonable to hypothesize a further extension of its indication even to elective and low-risk surgical patients.

[Mechanical ventilation and early weaning: a qualitative study on patient's experiences in an intensive care unit]. / Ventilazione meccanica ed estubazione precoce: studio qualitativo sul vissuto dei degenti di una terapia intensiva cardiochirurgia.

SUMMARY: Mechanical ventilation and early weaning: a qualitative study on patient's experiences in an intensive care unit. INTRODUCTION: The weaning from mechanical ventilation of intensive care unit (ICU) patients may cause anxiety. The feelings and experience during this procedure may affect their physical and psychological wellbeing. AIM: To describe patients' feelings during intubation time and weaning. METHOD: Phenomenological study on 16 patients who underwent an off pump bypass and mechanical ventilation <24 hours. The patients were contacted 5-7 days after discharge from ICU. RESULTS: The analysis of the interviews generated three issues arising from patients' experience: the discomfort mainly for the endotracheal tube, the fear of extubation and sense of safety for the presence of the nurse. CONCLUSIONS: Mechanical ventilation and weaning, in spite of the evolution of the anesthetic techniques, continue to generate unpleasant feelings.

Multiple composite grafts (k, π or double-Y) in coronary artery surgery: a choice or a necessity?

OBJECTIVES: Composite grafts allow complete arterial revascularization with minimal aortic manipulations. The Y-T configuration supplies all distal branches adequately, whereas it is unclear whether complex composite configurations (K, Π or double-Y) are equally at rest or when challenged by maximal requirements. METHODS: Forty-seven patients who underwent off-pump coronary artery revascularization by multiple arterial composite grafts (K, Π or double-Y) were retrospectively evaluated. Indication for this surgical option was porcelain aorta or conduit unavailability. Composite systems were evaluated by intraoperative flow measurements and perioperative transthoracic Doppler ultrasonography, 12 months later also by exercise test, sestamibi scintigraphy at rest and during induced hyperaemia and by 64-slice multidetector CT angiography. RESULTS: A total of 141 distal anastomoses were implanted as composite grafts. Perioperative flow measurements and 12-month Doppler ultrasonography were adequate at rest. At stress test, chest pain and/or induced ECG evidence of ischaemia are found in 16 patients (39%). During dipyridamole-induced hyperaemia, single-photon emission computed tomography image revealed that mean summed stress score was 7.2 ± 5.7, summed difference score 5.3 ± 4.2 and coronary flow reserve 1.7 ± 0.2. CONCLUSIONS: Multiple composite grafts, albeit adequate at rest, were unable to meet flow requirements during maximal hyperaemia. In daily practice, their use must be not a choice but rather a necessity in those patients without alternative options.

First experience with sildenafil after Fontan operation: short-term outcomes.

BACKGROUND: We conducted a retrospective study to determine the effect of oral sildenafil administrated as monotherapy after Fontan operation in single ventricle physiology. METHODS: From January 2008 to March 2012, during two different periods, a total of 30 pediatric patients undergoing Fontan operation by extracardiac conduit were included in this study. Thirteen patients were in the sildenafil group and exclusively treated with sildenafil given at the dose of 0.35 mg/kg through a nasogastric tube and then orally every 4 h, at the start of cardiopulmonary bypass and for the first postoperative week; then we reduced and discontinued the therapy. The other 17 patients were in the control group. No other vasodilator was administered in both groups. We analyzed intraoperative and postoperative outcomes of sildenafil administration. RESULTS: There were no differences in mortality or operative time. The total and relative drainage loss was lower in the sildenafil group (P = 0.0003 and 0.0045). The hemodynamic parameters showed a better condition in the sildenafil group, with a lower mean pulmonary artery pressure (mPAP) (P = 0.0001) and better mPAP to mean systemic blood pressure (mSBP) ratio (P = 0.0043), whereas there was no difference in peripheral oxygen saturation (P = 0.31). The sidenafil group patients showed other additional positive differences as well as lower inotropic score (P = 0.0005) and intubation time (P = 0.0004). No complications related to the use of sildenafil were noted in any of the children studied. CONCLUSION: This initial experience provides evidence that sildenafil may be used in postoperative Fontan operation with positive effectiveness.

Late-onset Blalock-Taussig shunt occlusion due to a subclavian artery pseudoaneurysm.

A 3-month-old infant with tetralogy of Fallot presented with progressive severe cyanosis and intractable acidosis about 2 months after a successful modified right-sided Blalock-Taussig shunt. At cardiac catheterization, the suspected shunt malfunction was confirmed. It was due to a bulky, pear-like mass arising from the right subclavian artery and compressing the polytetrafluoroethylene conduit. Any attempt to recanalize the shunt by percutaneous techniques proved unsuccessful. At surgery, a huge dilation of the anterior wall of the right subclavian artery, that sharply bent the prosthetic conduit, was found. Pathologic examination revealed that the compressing mass was pseudo-aneurysmal in nature. Despite a second successful shunt operation with a dramatic clinical improvement, the patient died due to multiorgan failure 72 hours following surgery. Extrinsic compression by a false aneurysm is a rare cause of shunt occlusion that should always be suspected in patients presenting with a rapidly progressive shunt malfunction late after a successful shunt procedure.

Individualized strategy for clopidogrel suspension in patients undergoing off-pump coronary surgery for acute coronary syndrome: a case-control study.

OBJECTIVE: An increasing number of patients presenting for urgent coronary surgery have been exposed to clopidogrel, which constitutes a risk of bleeding and related events. Based on the wide variability in clopidogrel response and platelet function recovery after cessation, we evaluated the role of point-of-care platelet function testing to define the optimal time for off-pump coronary artery bypass graft (CABG) surgery in a case-control study. METHODS: Three equally matched groups (300 patients in total) undergoing isolated off-pump CABG for acute coronary syndrome were compared. Group A were treated with clopidogrel and prospectively underwent a strategy guided by platelet function testing. Outcomes were compared with 2 propensity score matched groups: group B underwent CABG after the currently recommended 5 days without clopidogrel; group C were never exposed to clopidogrel. RESULTS: Patients in group A had reduced postoperative bleeding compared with those in group B (523±202 mL vs 851±605 mL; P<.001) and a lower number of units packed red blood cells (PRBCs) transfused during the postoperative hospital stay (1.2±1.6 units vs 1.9±1.8 units; P=.004). Postoperative bleeding and the number of units of PRBCs transfused were similar in group A and group C. There was no difference in blood-derived products and platelet consumption, mortality, or the need for reoperation among the groups. Patients in group A waited 3.6±1.7 days for surgery. The strategy used for group A saved 280 days of hospital stay in total. CONCLUSIONS: The strategy guided by platelet function testing for off-pump CABG offers improved guidance for optimal timing of CABG in patients treated with clopidogrel. This strategy significantly reduces postoperative bleeding and blood consumption, and has a shorter waiting time for surgery than current clinical practice.

Continuative statin therapy after percutaneous coronary intervention improves outcome in coronary bypass surgery: a propensity score analysis of 2501 patients.

OBJECTIVES: A history of percutaneous coronary intervention increases the risk of death and complications of coronary artery bypass grafting. This retrospective multicenter study evaluated the impact of continuative use of statin on postoperative outcomes when subsequent elective coronary artery bypass grafting is required after percutaneous coronary intervention. METHODS: Among 14,575 patients who underwent isolated first-time coronary artery bypass grafting between January 2000 and December 2010, 2501 who had previous percutaneous coronary intervention with stenting and fulfilled inclusion criteria were enrolled. Continuative statin therapy was used in 1528 patients and not used in 973 patients. Logistic multiple regression and propensity score analyses were used to assess the risk-adjusted impact of statin therapy on in-hospital mortality and major adverse cardiac events. The Cox proportional hazards model was constructed to assess the effect of continuative statin therapy on 24-month outcome. RESULTS: At multivariate analysis, age more than 70 years, 3-vessel or 2-vessel plus left main coronary disease, multivessel percutaneous coronary intervention, ejection fraction 0.40 or less, diabetes mellitus, and logistic European System for Cardiac Operative Risk Evaluation 5 or greater were independent predictors of hospital mortality and major adverse cardiac events. After propensity score matching, conditional logistic regression analysis demonstrated that continuative statin therapy before coronary artery bypass grafting reduced the risk for hospital and 2-year mortality (odds ratio [OR], 0.27; 95% confidence interval [CI], 0.12-0. 57; P=.004 and OR, 0.6; 95% CI, 0.36-0.96; P=.04, respectively) and major adverse cardiac events (OR, 0.31; 95% CI, 0.18-0.78; P=.003 and OR, 0.5; 95% CI, 0.34-0.76; P=.006, respectively). CONCLUSIONS: Long-term statin treatment after percutaneous coronary intervention improves early and midterm outcome when surgical revascularization will be required.

Y grafts with the left internal mammary artery and radial artery. Mid-term functional and angiographic results. Cohort study.

BACKGROUND: This retrospective cohort study investigated the functional and haemodynamic mid-term results over 3-years follow up of the left internal mammary artery (LIMA) conduit in composite Y-graft configuration with radial artery (RA) in a population of patients who underwent off-pump coronary artery bypass grafting (CABG). METHODS: 148 patients who underwent off-pump CABG with composite Y-graft, were evaluated over 3-year follow up. Two-day dipyridamole induced maximal hyperaemia/rest 99mTc-sestamibi was scheduled preoperatively and 36 months after surgery for functional evaluation. Morphological evaluation was performed by 64 slice multidetector computed tomography (CT) 36 months after surgery. RESULTS: Clinical adverse events were rare within 3 years follow up. Minimal to severe scintigraphic evidence of stress induced ischaemia occurred in 24 patients. Left ventricular (LV) hypertrophy (HR 3.1; 95% CI, 1.5-9.3; p = 0.01) and poor coronary run off (HR 4.1; 95% CI, 2.1-10.8; p = 0.005) were significant multivariate predictors of reversible stress induced ischaemia. 64 slice multidetector CT showed that the main stem of Y composite grafts was patent in all patients, while distal LIMA or RA was stenosed or occluded in 9 patients. CONCLUSION: Composite Y-graft was adequate to meet the flow requirements of target coronary artery either at rest or during maximal hyperaemia. The use of Y-graft should be carefully evaluated in patients with LV hypertrophy and/or poor coronary run-off.

Asymmetric septal hypertrophy in patients with severe aortic stenosis: the usefulness of associated septal myectomy.

OBJECTIVE: Asymmetric septal hypertrophy frequently coexists with severe aortic stenosis and can be unmasked after successful aortic valve replacement (AVR), jeopardizing the clinical and echocardiographic results. The aim of our study was to investigate, at 5 years postoperatively, the effectiveness of myectomy associated with AVR on left ventricular (LV) mass regression and LV diastolic function. METHODS: From 1997 and 2004, 86 patients with a diagnosis of severe aortic stenosis and asymmetric septal hypertrophy consecutively underwent AVR (group A) or AVR and concomitant myectomy (group B). To assess the improvement in LV mass and LV diastolic function, we studied the 52 survivors (23 in group A and 29 in group B) who had the same prosthesis type (beleaflet mechanical), the same size (21 mm), and the same follow-up length. RESULTS: In group A, the LV mass index regressed from 119.2 ± 22.0 to 113.8 ± 21.8, and in group B, it regressed from 121.6 ± 20.8 to 112.7 ± 20.0 (P < .0005). In group A, the E/E' ratio improved from 15.3 ± 3.0 to 11.8 ± 3.0, and in group B, it improved from 16.2 ± 3.2 to 12.1 ± 3.3 (P = .02). CONCLUSIONS: Surgeons should inspect the LV outflow tract at AVR. Concomitant myectomy at AVR is a safe and effective procedure that improves LV mass regression and LV diastolic function.

Doxycycline prevents intimal hyperplasia in vitro and may improve patency of the internal thoracic artery.

OBJECTIVES: The development of intimal hyperplasia and graft failure is an important problem in cardiac surgery. A fundamental process in intimal hyperplasia is the degradation of extracellular matrix by metalloproteases which induces the vascular smooth-muscle cells migration and sets the scene for graft atherosclerosis. This study investigated whether doxycycline, a metalloproteases inhibitor, can prevent the intimal hyperplasia occurrence in cultured human internal mammary artery, thus extending graft patency. METHODS: Segments of internal mammary artery from 20 consecutive patients were prepared and cultured for 2 weeks in serum-supplemented medium (control) or in medium supplemented with 10⁻5 M and 10⁻6 M doxycycline concentrations. Tissues were fixed, sectioned, and stained, and neointimal thickness was measured by computer-aided image analysis. Further sections were cultured and prepared for gel enzymography to measure the matrix metalloproteinase-2 and -9 levels. RESULTS: At the end of the culture period, neointimal thickness was significantly (P = 0.001) dose-dependently reduced in samples treated with doxycycline when compared with controls. Gelatin enzymography demonstrated a reduction in values for both latent and active forms of metalloproteases. CONCLUSIONS: Doxycycline, in a model of internal mammary artery intimal hyperplasia, has a specific role in inhibiting metalloproteases activity and may prevent graft stenosis.

B-type natriuretic peptide as a biochemical marker of left ventricular diastolic function: assessment in asymptomatic patients 1 year after valve replacement for aortic stenosis.

OBJECTIVES Left ventricular (LV) diastolic dysfunction after aortic valve replacement (AVR) carries a substantial risk of development of heart failure and reduced survival. In addition to echocardiography, B-type natriuretic peptide (BNP) provides a powerful incremental assessment of diastolic function. This study evaluates BNP as a marker of LV diastolic dysfunction in a cohort of patients with preserved LV ejection fraction who underwent AVR for pure aortic stenosis and the relationship between BNP values and the grade of LV diastolic dysfunction. METHODS A total of 113 patients were included in the study. Echocardiographic evaluation was performed preoperatively, 5 days postoperatively and at 12-month follow-up, to assess LV dimensional and functional parameters. Diastolic function was labelled as normal, mild, moderate or severe dysfunction. Concomitantly, BNP levels were evaluated. RESULTS Mild to severe diastolic dysfunction occurred preoperatively in all patients. At 12-month follow-up, 65 (62.5%) patients had mild and 25 (24.1%) moderate to severe diastolic dysfunction. BNP values, categorized for quartile distribution, correlated with diastolic dysfunction grade (P<0.001 for each comparison). At receiver operating characteristic analysis, the BNP level of 120 pg/ml was 91% sensitive and 85% specific for diastolic disease, while 300 pg/ml was 80% sensitive and 91% specific for moderate or severe diastolic dysfunction. Twelve months after AVR, BNP values were strongly correlated with the significant echocardiographic parameters suggestive of diastolic dysfunction (P≤0.006 in all cases). CONCLUSIONS The BNP level following AVR is related to diastolic disease severity and may complement echocardiographic evaluation when symptoms are unclear and LV function is difficult to interpret.

Coronary perfusion: impact of flow dynamics and geometric design of 2 different aortic prostheses of similar size.

BACKGROUND: Aortic valve replacement leads to improvement of coronary flow but not to complete normalization. Coronary hypoperfusion contributes to higher left ventricular mass persistence, arrhythmias, congestive heart failure and sudden death. This prospective study compares 2 similarly sized aortic prostheses (mechanical and porcine) regarding coronary flow and hemodynamic performances in patients who underwent surgery for pure aortic stenosis. METHODS: Sixty patients having undergone aortic valve replacement for pure aortic stenosis with Medtronic Mosaic Ultra bioprosthesis 21 mm (n = 30) or St Jude Regent mechanical valve 19 mm (n = 30) were evaluated preoperatively and 12 months postoperatively comparing the coronary flow and the hemodynamic behavior. Echocardiography and cardiac positron emission tomography were performed at rest and during exercise or adenosine maximal stimulation, respectively. RESULTS: The St Jude Regent mechanical valve, compared with the Medtronic Mosaic Ultra bioprosthesis, had reduced coronary flow reserve (2.1 ± 0.3 vs 2.3 ± 0.2; P = .003), less favorable systolic/diastolic time ratio (0.87 ± 0.02 vs 0.78 ± 0.03; P < .001), and higher mean transprosthetic gradient (46 ± 11 vs 38 ± 9; P = .003) during exercise. Multivariate analysis of impaired coronary reserve related indexed effective orifice area less than 0.65 cm/m(2) (risk ratio [RR], 1.9; 95% confidence intervals [CI], 1.5-2.8; P < .001), mechanical valve (RR, 2.5; 95% CI, 1.7-3.3; P < .001), and systolic/diastolic time ratio greater than 0.75 (RR, 2.6; 95% CI, 1.8-3.8; P < .001), as well as high transprosthetic gradient (RR, 1.7; 95% CI, 1.3-2.4; P < .001) ) during exercise with coronary reserve less than 2.2. CONCLUSIONS: Improvement of coronary flow and reserve was more evident for bioprostheses than for mechanical valves. The bioprostheses demonstrated superior hemodynamics during exercise, which may have some impact on exercise capability during normal daily life.

Myocardial metabolism and diastolic function after aortic valve replacement for aortic stenosis: influence of patient-prosthesis mismatch.

OBJECTIVE: This study evaluated the impact of patient-prosthesis mismatch on myocardial function and high-energy phosphate metabolism after aortic valve replacement for pure aortic stenosis. Patients with and without patient-prosthesis mismatch were compared using magnetic resonance techniques. METHODS: Thirty patients who had undergone aortic valve replacement with Medtronic Mosaic bioprosthesis were evaluated. Fifteen patients with patient-prosthesis mismatch were compared to 15 matched patients without patient-prosthesis mismatch. These two homogeneous groups were studied for myocardial metabolism and left ventricle function preoperatively and at 12 months postoperatively with magnetic resonance imaging and (31)P spectroscopy. RESULTS: All patients experienced improvement in myocardial metabolism and left ventricle function. Left ventricle mass regression was impaired in both groups. Impaired diastolic filling was associated with increased left ventricle wall mass in both groups (patient-prosthesis mismatch: R(2) = -0.71, p = 0.002; no patient-prosthesis mismatch: R(2) = -0.88, p < 0.001). Myocardial phosphocreatine/adenosine triphosphate ratio revealed a modest correlation with left ventricle function as evaluated by early acceleration peak (patient-prosthesis mismatch: R(2) = 0.37, p = 0.03; no patient-prosthesis mismatch: R(2) = 0.17, p = 0.02) and early deceleration peak (patient-prosthesis mismatch: R(2) = 0.30, p = 0.01; no patient-prosthesis mismatch: R(2) = 0.39, p = 0.008). No significant correlation between the phosphocreatine/adenosine triphosphate ratio and left ventricle mass was found (patient-prosthesis mismatch: R(2) = 0.39, p = 0.6; no patient-prosthesis mismatch: R(2) = 0.40, p = 0.08). CONCLUSION: Aortic valve replacement leads to early improvement of left ventricle function and myocardial metabolism in all patients regardless of the occurrence of patient-prosthesis mismatch.