Is a stentless aortic valve superior to conventional bioprosthetic valves for aortic valve replacement?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether a stentless valve is superior to conventional stented valves when tissue aortic valve replacement is performed. Altogether more than 515 papers were found using the reported search, of which 16 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. We conclude that stentless valves allow a larger effective orifice area valve to be implanted with a lower mean and peak aortic gradient postoperatively. At six months several studies and a meta-analysis have shown superior left ventricular mass regression in the stentless valve groups. However, by 12 months the stented valve groups catch up in terms of mass regression and this significance disappears. So the 'eminent speaker from the floor', was right with his statement, that there have been no definitively proven benefits for stentless valves.     

Is prophylactic aortic valve replacement indicated during mitral valve surgery for mild to moderate aortic valve disease?

BACKGROUND: Determining the need for surgical treatment of coexisting mild to moderate aortic valve disease in patients referred for mitral valve surgery is often difficult. The purpose of this study was to assess long-term clinical outcome and the need for subsequent aortic valve replacement in patients with mild to moderate rheumatic aortic valve disease at the time of mitral valve surgery. METHODS: A total of 275 patients (90 men and 185 women, mean age 43 years) with rheumatic disease who underwent mitral valve surgery were followed up for an average of 9 years. Patients were classified into two groups: those with coexisting mild to moderate aortic valve disease at the time of mitral valve surgery (141 patients, group A) and those without (134 patients, group B). Primary outcomes (death and subsequent aortic valve surgery) were compared between the two groups. RESULTS: At the time of mitral valve surgery, 104 patients (74%) in group A had mild aortic regurgitation, 37 (26%) had moderate aortic regurgitation, 5 had (4%) mild aortic stenosis, and 2 (1%) had moderate aortic stenosis. At the end of follow-up, no patient had severe aortic valve disease. In all, 12 patients (5%) in group A had primary events (eight deaths and four subsequent aortic valve replacements), and 12 patients (9%) in group B had such events (12 deaths). According to Kaplan-Meier analysis, neither the survival rate nor the event-free survival rate differed significantly over the follow-up period between the two groups. CONCLUSIONS: In most patients who have mild to moderate rheumatic aortic valve disease at the time of mitral valve surgery, the long-term outcome is comparable to that of subjects without aortic valve disease at the time of mitral valve surgery. Subsequent aortic valve replacement is rarely needed after a long follow-up period.     

Optimal timing of aortic valve replacement for aortic stenosis--are we operating late?

OBJECTIVE: To evaluate the adherence to current guidelines for surgery in patients with aortic valve stenosis. DESIGN: From 1 January 1997 to 31 May 1999, 99 patients were accepted for aortic valve surgery with preserved left ventricular function and normal coronary angiogram. On admission for operation, 20 patients were evaluated regarding symptoms, exercise capacity, and left ventricular morphology and function. RESULTS: There were 14 men and 6 women, mean age 64.3 years. Years from symptom onset varied from 2.1 to 3.2. Dyspnoea was the most common limiting symptom. Thirty per cent of the patients were classified as NYHA IIIB. Physical capacity was reduced to 79% of the expected. Left ventricular hypertrophy was present in 14/20 patients. Left ventricular systolic function was reduced with mean ejection fraction of 0.46. Diastolic dysfunction (E/A ratio <1) was present in 12 patients. CONCLUSION: Many patients accepted for aortic valve replacement due to aortic stenosis show advanced disease and are referred for surgery later in the disease process than is recommended in the current guidelines.     

Is routine computed tomography angiography justified in patients undergoing aortic valve replacement for bicuspid aortic valve disease?

Background

Role of Computed Tomography Angiography (CTA) in patients with Bicuspid Aortic Valve (BAV) undergoing Aortic Valve Replacement (AVR) needs assessment.

Patients and Methods

After echocardiography, 54 patients with BAV were referred for AVR. CTA was performed routinely. Pre-operative characteristics, echocardiographic and CTA findings, and details of surgery were obtained.

Results

The study population had 54 subjects (48 males). Median age was 35.5 years (range 7 to 78 years), and median weight was 57.5 Kg (range 14 to 83 kg). On echocardiography, aortic sinus diameter ranged from 13 to 38 mm (median 28 mm). In none of the patients, ascending aorta was reported to be dilated. On CT angiography, the sinus diameter ranged from 16 to 46 mm (median 35 mm). Sinus diameter was ≥40 mm in 13 patients. The sinus diameter on echocardiography was within the range of 0 to 2 mm of CT angiographic estimates in 31 patients, within 2.1 to 5 mm in 22 patients, and more than 5 mm in one patient. The ascending aortic diameter ranged from 19 to 70 mm (median 43 mm). In 26 patients, ascending aortic diameter was ≥45 mm. In 12 patients, the proximal arch diameter was ≥40 mm. In two patients, the distal ascending aorta and proximal arch were aneurysmally dilated (48 mm and 57 mm). In 12 patients, the ascending aorta was dilated (≥ 45 mm) without any sinus dilatation. In one patient, the distal ascending aorta and proximal arch were aneurysmally dilated (57 mm) without any proximal dilatation. Based on CT angiographic findings, 25 patients (46.3 %) underwent additional aortic replacement in the form of Bentall’s procedure (n?=?7), Bentall’s + Hemiarch replacement (n?=?6), aortoplasty (n?=?5), Wheat procedure (n?=?6) and Wheat procedure?+?Hemiarch replacement (n?=?1).

Conclusion

CT angiography is justified as a routine pre-operative evaluation tool in all patients with BAV who are undergoing open heart surgery for significant aortic valve dysfunction.     

In patients with concomitant aortic and mitral valve disease is aortic valve replacement with mitral valve repair superior to double valve replacement?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was: in patients with concomitant aortic and mitral valve disease is aortic valve replacement with mitral valve plasty (MVP) superior to double valve replacement (DVR) in terms of improved long-term survival? Altogether 156 papers were found using the reported search, of which seven represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Out of seven papers, that simultaneously compare these two treatment modalities, three favor MVP combined with aortic valve replacement (AVR) over DVR, two papers advocate the opposite and two failed to find any significant difference in long-term survival, freedom from reoperation and thromboembolic and bleeding complications between these two surgical options. All data presented derive from level 2b evidence. Critical appraisal of these studies is constricted by the large heterogeneity of the patients, diversity in treatment protocols and inherent selection bias. We conclude that currently the available evidence is insufficient to prove that AVR with MVP is superior to DVR in patients with double valve disease.     

Should warfarin be routinely prescribed for the first three months after a bioprosthetic valve replacement?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether warfarin should be routinely prescribed for the first three months after a bioprosthetic valve replacement either for the aortic or mitral position. Altogether 620 papers were identified using the below-mentioned search. In addition, all major international guidelines were included. Fifteen papers presented the best evidence to answer the clinical question. The author, journal, date and country of publication, patient group, relevant outcomes and weaknesses were tabulated. We conclude that all guidelines, the available evidence and current practice support the use of warfarin at an INR of 2-3 for 3 months for bioprosthetic mitral valve replacement (MVR). However, it must be acknowledged that this recommendation is based on only a small number of non-randomized cohort studies and on expert consensus. For patients without high risk factors undergoing a bioprosthetic aortic valve replacement (AVR), the European Society of Cardiology (ESC), the American College of Chest Physicians (ACCP) and the Scottish Intercollegiate Guidelines Network (SIGN) all recommend warfarin for 3 months after surgery. However, the American Heart Association (AHA/ACC) guidelines and the British Society for Haematology (BSH) regard aspirin alone as adequate therapy. In addition, two large surveys show that the majority of surgeons worldwide now use only antiplatelet therapy. The evidence from clinical studies to support the use of warfarin post-bioprosthetic AVR is very weak and out-dated, and therefore, we feel that it is certainly safe to use antiplatelet therapy alone post-bioprosthetic AVR.     

Should the transverse aortic arch be replaced simultaneously with aortic root replacement for annuloaortic ectasia in Marfan syndrome?

OBJECTIVE: The purpose of this study was to determine, on the basis of the late fate of the intact aortic arch with abnormal tissue after aortic root replacement, whether the intact aortic arch should be replaced prophylactically at the time of aortic root replacement for annuloaortic ectasia in Marfan syndrome. METHODS: A retrospective review was performed in 85 patients with Marfan syndrome who underwent aortic root replacement for annuloaortic ectasia with or without aortic dissection (mean age 37 years, range 19-61 years). These 85 patients were divided into four groups according to the postoperative condition of the residual aorta. In group I (n = 47), the patients underwent aortic root replacement for annuloaortic ectasia with or without localized dissection in the ascending aorta. In these patients the residual aorta, including the aortic arch, was therefore intact. In group II (n = 10), the aortic arch was intact, although the descending thoracic aorta was dissected because of the preoperative type B dissection. In groups III and IV, the patients had type A dissection involving the transverse arch associated with annuloaortic ectasia. In group III (n = 13), residual dissection existed in the descending thoracic aorta after concomitant total arch replacement. In group IV (n = 15), the aortic arch and the descending thoracic aorta were dissected. RESULTS: There were 5 early deaths (3 in group I, 1 in group II, and 1 in group III). Subsequent operations were required in 10, 5, 6, and 7 cases in groups I, II, III, and IV, respectively. Regarding the aortic arch, only 2 of 53 survivors of the initial hospitalization with an intact aortic arch (groups I and II) underwent subsequent total arch replacement for the onset of dissection in the aortic arch, and 4 of 14 survivors of the initial hospitalization with a residual dissecting arch (group III) needed subsequent total arch replacement. Actuarial freedom from arch repair among patients with an intact aortic arch (91% at 15 years) was significantly higher than that among patients with a residual dissecting arch (49% at 15 years, P =.0078). CONCLUSIONS: The incidence of new dissection in the residual intact arch after aortic root replacement was extremely low. Therefore prophylactic replacement of the intact arch does not appear to be necessary at aortic root replacement for annuloaortic ectasia in Marfan syndrome.     

Sleeve gastrectomy to aortic valve replacement: safe?

BackgroundBariatric surgery has favorable results on cardiac structure and function, but there is minimal research on its utility in the cardiac comorbid population.ObjectivesTo determine if laparoscopic sleeve gastrectomy (SG) is safe in patients with symptomatic aortic stenosis (AS).SettingCommunity hospital/bariatric center of excellence in Pennsylvania.MethodsRetrospective single center review of 18 patients with morbid obesity and clinically significant AS. All SGs were performed between June 2016 and June 2020. Outcomes including hospital length of stay, 30-day readmission, and 30-day mortality in the study population (n = 18) were compared with 100 patients without AS who underwent SG at the same institution during the same time.ResultsThere were no perioperative deaths. Mean hospital stay in the study group was 1.78 days compared with 1.3 days in the noncardiac group (P = .1154). Two of 18 patients (11.1%) required readmission within 30 days, both for clinically significant bleeding, compared with 2 of 100 noncardiac patients (2.0%) (P = .1097). Seventeen of 18 study patients went on to have definitive aortic valve replacement surgery.ConclusionSG appears safe in patients with clinically significant AS. Although the AS group did have a higher rate of complications, these were manageable and did not increase mortality or LOS. Further studies are required to determine if outcomes of definitive aortic valve replacement are improved after bariatric surgery.     

Aortic valve replacement for aortic stenosis in patients with concomitant mitral regurgitation: should the mitral valve be dealt with?

Co-existent mitral regurgitation may adversely influence both morbidity and mortality in patients undergoing aortic valve replacement for severe aortic stenosis. Whilst it is accepted that concomitant mitral intervention is required in severe, symptomatic mitral regurgitation, in cases of mild–moderate non-structural mitral regurgitation, improvement may be seen following aortic valve replacement alone, avoiding the increased risk of double-valve surgery. The exact benefit of such a conservative approach is, however, yet to be adequately quantified. We performed a systematic literature review identifying 17 studies incorporating 3053 patients undergoing aortic valve replacement for aortic stenosis with co-existing mitral regurgitation. These were meta-analysed using random effects modelling. Heterogeneity and subgroup analysis were assessed. Primary end points were change in mitral regurgitation severity and 30-day, 3-, 5- and 10-year mortality. Secondary end points were end-organ dysfunction (neurovascular, renal and respiratory), and the extent of ventricular remodelling following aortic valve replacement. Our results revealed improvement in the severity of mitral regurgitation following aortic valve replacement in 55.5% of patients, whereas 37.7% remained unchanged, and 6.8% worsened. No significant difference was seen between overall data and either the functional or moderate subgroups. The overall 30-day mortality following aortic valve replacement was 5%. This was significantly higher in moderate–severe mitral regurgitation than nil–mild mitral regurgitation both overall (p = 0.002) and in the functional subgroup (p = 0.004). Improved long-term survival was seen at 3, 5 and 10 years in nil–mild mitral regurgitation when compared with moderate–severe mitral regurgitation in all groups (overall p < 0.0001, p < 0.00001 and p = 0.02, respectively). The relative risk of respiratory, renal and neurovascular complications were 7%, 6% and 4%, respectively. Reverse remodelling was demonstrated by a significant reduction in left-ventricular end-diastolic diameter and left-ventricular mass (p = 0.0007 and 0.01, respectively), without significant heterogeneity. No significant change was seen in left-ventricular end-systolic diameter (p = 0.10), septal thickness (p = 0.17) or left atrial area (p = 0.23). We conclude that despite reverse remodelling, concomitant moderate–severe mitral regurgitation adversely affects both early and late mortality following aortic valve replacement. Concomitant mitral intervention should therefore be considered in the presence of moderate mitral regurgitation, independent of the aetiology.     

Do patients want minimally invasive aortic valve replacement?

Objective: Access to aortic valve can be performed through small incisions. However, a considerable advantage of this approach has not been proven by randomized studies so far. We wanted to elucidate the opinion of patients when they are informed objectively about advantages and disadvantages of minimally invasive approach prior to operation. Methods: This prospective study was performed with 27 patients undergoing isolated aortic valve replacement. These patients were informed prior to operation by the same resident concerning objective data. A photograph was shown illustrating a patient with postoperative wound after a standard- and a mini-incision, respectively. After the interview the patient could decide between full and partial sternotomy. Results: After the interview 21/27 (78%) patients preferred to have a full sternotomy (group F) and 6/27 (22%) patients (group P) decided to have a partial sternotomy. Comments of group F: surgeon should have best exposure (n=15); cosmetics aspects unimportant (n=14); operation time as short as possible (n=7). Group P: cosmetic aspects important (n=6). Significant differences between groups (group F vs. group P): age (years), 69.1±1.5 vs. 49.2±7.3 (P=0.024); operation time (min), 142±7 vs. 189±15 (P=0.002); CK (IU/l), 111±11 vs. 374±114 (P=0.0007); CKMB (IU/l), 17±2 vs. 45±17 (P=0.006); ICU-stay (days), 2.6±0.2 vs. 3.2±0.2 (P=0.044). Pericardial effusion requiring drainage was observed in two patients of group P. One patient of group P suffered myocardial infarction. Conclusion: When patients are informed objectively about advantages and disadvantages of minimal invasive aortic valve surgery only a smaller number decides to have a mini incision. The patients preferring short incisions are significantly younger since cosmetic aspects are more important. Longer duration of operation may be due to longer hemostasis based on limited exposure. Air bubbles due to inadequate de-airing might be responsible for higher CK and CK-MB levels in group P.     

Selection of the prosthesis for aortic valve replacement: mechanical or bio?

To clarify the effect of the valve selection on the patients' prognosis, long-term outcome of the patients undergone isolated aortic valve replacement (AVR) with the mechanical or bioprosthetic valve in our institution were investigated. In protocol 1, patients of all ages with isolated AVR (n = 472, composed of 166 who received a bioprosthesic valve [group B] and 306 who received a mechanical valve [Group MI) between 1975 and 2004 were investigated. In protocol 2, primary AVR patients aged 50-65 years (n = 184, composed of 47 in group B and 137 in group M) were compared. There were no significant differences in freedom from cardiac death, freedom from bleeding, and freedom from endocarditis in Protocols 1 and 2. Significantly fewer redo AVRs were required in group M in both protocols 1 and 2. However, group M was significantly worse in terms of freedom from thromboembolism in protocol 2. As a result, group M was superior to group B in freedom from valve-related events when redo AVR included. When redo AVR was excluded, there was no difference between the two groups in freedom from valve-related events in both protocols 1 and 2. There may thus be an advantage in selecting bioprosthetic valves in young adult patients who required AVR if they accepts the possibility of redo AVR in future.