Outcome of combined stenotic and regurgitant aortic valve disease

This study sought to describe the natural history of combined stenotic and regurgitant aortic valve disease.

Proteomic alterations in heat shock protein 27 and identification of phosphoproteins in ascending aortic aneurysm associated with bicuspid and tricuspid aortic valve

Whether or not there are molecular differences, at the intra- and extracellular level, between aortic dilatation in patients with bicuspid (BAV) and those with a tricuspid aortic valve (TAV) has remained controversial for years. We have performed 2-dimensional gel electrophoresis and mass spectrometry coupled with dephosphorylation and phosphostaining experiments to reveal and define protein alterations and the high abundant structural phosphoproteins in BAV compared to TAV aortic aneurysm samples. 2-D gel patterns showed a high correlation in protein expression between BAV and TAV specimens (n=10). Few proteins showed significant differences, among those a phosphorylated form of heat shock protein (HSP) 27 with significantly lower expression in BAV compared to TAV aortic samples (p=0.02). The phosphoprotein tracing revealed four different phosphoproteins including Rho GDP dissociation inhibitor 1, calponin 3, myosin regulatory light chain 2 and four differentially phosphorylated forms of HSP27. Levels of total HSP27 and dually phosphorylated HSP27 (S78/S82) were investigated in an extended patient cohort (n=15) using ELISA. Total HSP27 was significantly lower in BAV compared to TAV patients (p=0.03), with no correlation in levels of phospho-HSP27 (S78/S82) (p=0.4). Western blots analysis showed a trend towards lower levels of phospho-HSP27 (S78) in BAV patients (p=0.07). Immunohistochemical analysis revealed that differences in HSP27 occur in the cytoplasma of VSMC's and not extracellularly. Alterations in HSP27 may give early evidence for intracellular differences in aortic aneurysm of patients with BAV and TAV. Whether HSP27 and the defined phosphoproteins have a specific role in BAV associated aortic dilatation remains to be elucidated.

Resuspension of the aortic valve in acute type A dissection: long-term results

BACKGROUND AND AIM OF THE STUDY: Preservation of the aortic valve during the repair of acute type A aortic dissection (AADA) is a viable option to prevent lifelong oral anticoagulation. The study aim was to assess aortic valve function following resuspension and supracoronary ascending aortic grafting. METHODS: Among a collective of 210 consecutive patients undergoing surgery for AADA, 140 (66.7%) with resuspension of the aortic valve and supracoronary ascending graft were analyzed. Of these patients, 83 (59.3%) had a complete follow up (mean 61.2 +/- 40.8 months), with 65 of the subgroup (78.3%) being followed by computed tomography scanning and echocardiography. RESULTS: Reoperation due to severe aortic valve regurgitation was required in seven patients (10.8%). The perioperative characteristics were similar in these patients; notably, no significant difference was evident with regards to the aortic annulus diameter and the severity of regurgitation at the time of surgery. The left ventricular mass index was significantly higher in patients requiring reoperation due to aortic valve regurgitation (219.3 +/- 146.6 versus 123.9 +/- 146.6 g/m2; p <0.05). None of the patients died as a result of reoperation. CONCLUSION: The long-term functional results following resuspension of the aortic valve in AADA were very good. A close echocardiographic follow up was necessary, as reoperation of the aortic valve was required in more than 10% of the collective, with an average follow up of five years. Reoperation was mainly related to secondary dilatation of the aortic root.

Clinical and hemodynamic predictors of natriuretic peptide elevation among aortic valve disease patients

We investigated the relative contribution of hemodynamic and clinical factors to serum natriuretic peptide elevation in seventy-one patients with either aortic stenosis or aortic regurgitation. We found that pulmonary hypertension, heart failure and renal failure are the most powerful independent predictors of natriuretic peptide elevation in patients with aortic valve disease, irrespective of the type or severity of valvular lesion itself.

Massive intraoperative thrombus of the aortic arch and proximal descending aorta

A 49-year-old male patient presented with a paravalvular leakage 18 years after aortic valve replacement. The patient received a mechanical valve and was weaned uneventfully from cardiopulmonary bypass. After a drop in the pressure curve of the left radial artery an additional line was placed in the proximal ascending aorta showing normal systemic pressure. Transesophageal echocardiography showed a massive circular thrombosis of the distal aortic arch. The patient received a covered stent to expand the residual aortic lumen and left the hospital in good health.

Valved stents for transapical pulmonary valve replacement

OBJECTIVES: Pulmonary valve insufficiency remains a leading cause for reoperations in congenital cardiac surgery. The current percutaneous approach is limited by the size of the access vessel and variable right ventricular outflow tract morphology. This study assesses the feasibility of transapical pulmonary valve replacement based on a new valved stent construction concept. METHODS: A new valved stent design was implanted off-pump under continuous intracardiac echocardiographic and fluoroscopic guidance into the native right ventricular outflow tract in 8 pigs (48.5 +/- 6.0 kg) through the right ventricular apex, and device function was studied by using invasive and noninvasive measures. RESULTS: Procedural success was 100% at the first attempt. Procedural time was 75 +/- 15 minutes. All devices were delivered at the target site with good acute valve function. No valved stents dislodged. No animal had significant regurgitation or paravalvular leaking on intracardiac echocardiographic analysis. All animals had a competent tricuspid valve and no signs of right ventricular dysfunction. The planimetric valve orifice was 2.85 +/- 0.32 cm(2). No damage to the pulmonary artery or structural defect of the valved stents was found at necropsy. CONCLUSIONS: This study confirms the feasibility of direct access valve replacement through the transapical procedure for replacement of the pulmonary valve, as well as validity of the new valved stent design concept. The transapical procedure is targeting a broader patient pool, including the very young and the adult patient. The device design might not be restricted to failing conduits only and could allow for implantation in a larger patient population, including those with native right ventricular outflow tract configurations.

Total surgical aortic arch replacement as a safe strategy to treat complex multisegmental proximal thoracic aortic pathology.

OBJECTIVE To analyse the results after elective open total aortic arch replacement. METHODS We analysed 39 patients (median age 63 years, median logistic EuroSCORE 18.4) who underwent elective open total arch replacement between 2005 and 2012. RESULTS In-hospital mortality was 5.1% (n = 2) and perioperative neurological injury was 12.8% (n = 5). The indication for surgery was degenerative aneurysmal disease in 59% (n = 23) and late aneurysmal formation following previous surgery of type A aortic dissection in 35.9% (n = 14); 5.1% (n = 2) were due to anastomotical aneurysms after prior ascending repair. Fifty-nine percent (n = 23) of the patients had already undergone previous proximal thoracic aortic surgery. In 30.8% (n = 12) of them, a conventional elephant trunk was added to total arch replacement, in 28.2% (n = 11), root replacement was additionally performed. Median hypothermic circulatory arrest time was 42 min (21-54 min). Selective antegrade cerebral perfusion was used in 95% (n = 37) of patients. Median follow-up was 11 months [interquartile range (IQR) 1-20 months]. There was no late death and no need for reoperation during this period. CONCLUSIONS Open total aortic arch replacement shows very satisfying results. The number of patients undergoing total arch replacement as a redo procedure and as a part of a complex multisegmental aortic pathology is high. Future strategies will have to emphasize neurological protection in extensive simultaneous replacement of the aortic arch and adjacent segments.

Coronary revascularization and TAVI: before, during, after or never?

Aortic valve stenosis and coronary artery disease (CAD) frequently coexist in elderly patients selected for transcatheter aortic valve implantation (TAVI). Therapeutic strategies to manage concomitant obstructive CAD are therefore an important consideration in the overall management of patients with severe aortic stenosis (AS) undergoing TAVI. Conventional surgical aortic valve replacement and coronary artery bypass grafting is the treatment of choice for low and intermediate risk patients with symptomatic severe AS and concomitant obstructive CAD. However, TAVI and percutaneous coronary intervention (PCI) are viable alternative options for high-risk or inoperable patients presenting with symptomatic severe AS. PCI has been shown to be feasible and safe in selected high-risk or inoperable patients with symptomatic severe AS. However, the optimal timing of PCI relative to the TAVI procedure has been a subject of debate. The most frequent approch is staged PCI typically performed a few weeks prior to TAVI. However, concomitant PCI has also been shown to be a feasible and safe approach, particularly in patients with a low level of CAD complexity and an absence of severe renal impairment. Conversely, staged PCI should be considered in patients with higher degrees of CAD complexity, particularly in the presence of severe renal impairment. The aim of the present review is to discuss the safety and feasibility of performing PCI in elderly patients with severe AS and the optimal timing of PCI relative to the TAVI procedure using the most up-to-date available evidence.

Coronary artery disease in patients undergoing TAVI: why, what, when and how to treat.

Coronary artery disease (CAD) and aortic valve stenosis (AS) are frequently coexisting. It has been reported that CAD is present in 40% of patients with AS undergoing surgical aortic valve replacement, and in up to 60% of patients with AS undergoing transcatheter aortic valve implantation (TAVI). Elderly patients with CAD and AS are characterised by higher baseline risk profiles as compared to patients with isolated AS, increasing the complexity of their therapeutic management. In patients with CAD and AS the combination of coronary artery bypass grafting (CABG) and surgical aortic valve replacement has been shown to improve survival. Therefore, CABG is recommended in patients with CAD and AS undergoing surgical aortic valve replacement according to current guidelines of the European Society of Cardiology (ESC) and of the American College of Cardiology Foundation/American Heart Association (ACCF/AHA). Conversely, whether the presence of CAD has any prognostic implications in elderly patients with severe AS undergoing TAVI is still a matter of debate. Of note, according to the most recent ESC guidelines on myocardial revascularisation, percutaneous revascularisation should be considered in patients undergoing TAVI with a stenosis >70% in proximal coronary segments (class IIa, level of evidence C). The aim of this article is to provide an overview of evidence supporting the need for coronary revascularisation in patients with severe AS and CAD undergoing TAVI, and to summarise optimal timing and treatment modalities for percutaneous coronary interventions in these patients.

Assessment of low-flow, low-gradient, severe aortic stenosis: an invasive evaluation is required for decision making.

Low-flow, low-gradient severe aortic stenosis (AS) is characterised by a small aortic valve area (AVA) and low mean gradient (MG) secondary to a low cardiac output and may occur in patients with either a preserved or reduced left ventricular ejection fraction (LVEF). Symptomatic patients presenting with low-flow, low-gradient severe AS have a dismal prognosis independent of baseline LVEF if managed conservatively and should therefore undergo aortic valve replacement if feasible. Transthoracic echocardiography (TTE) is the first-line investigation for the assessment of AS haemodynamic severity. However, when confronted with guideline-discordant AVA (small) and MG (low) values, there are several reasons other than severe AS combined with a low cardiac output which may lead to such a situation, including erroneous measurements, small body size, inherent inconsistencies in the guidelines' criteria, prolonged ejection time and aortic pseudostenosis. The distinction between these various entities poses a diagnostic challenge. However, it is important to make a distinction because each has very different implications in terms of risk stratification and therapeutic management. In such instances, cardiac catheterisation forms an integral part of the work-up of these patients in order to confirm or refute the echocardiographic findings to guide management decisions appropriately.

Preinterventional screening of the TAVI patient: how to choose the suitable patient and the best procedure.

Transcatheter aortic valve implantation (TAVI) is a novel therapy, which has transformed the management of inoperable patients presenting with symptomatic severe aortic stenosis (AS). It is also a proven and less invasive alternative therapeutic option for high-risk symptomatic patients presenting with severe AS who are otherwise eligible for surgical aortic valve replacement. Patient age is not strictly a limitation for TAVI but since this procedure is currently restricted to high-risk and inoperable patients, it follows that most patients selected for TAVI are at an advanced age. Patient frailty and co-morbidities need to be assessed and a clinical judgment made on whether the patient will gain a measureable improvement in their quality of life. Risk stratification has assumed a central role in selecting suitable patients and surgical risk algorithms have proven helpful in this regard. However, limitations exist with these risk models, which must be understood in the context of TAVI. When making final treatment decisions, it is essential that a collaborative multidisciplinary "heart team" be involved and this is stressed in the most recent guidelines of the European Society of Cardiology. Choosing the best procedure is contingent upon anatomical feasibility, and multimodality imaging has emerged as an integral component of the pre-interventional screening process in this regard. The transfemoral route is now considered the default approach although vascular complications remain a concern. A minimal vessel diameter of 6 mm is required for currently commercial available vascular introducer sheaths. Several alternative access routes are available to choose from when confronted with difficult iliofemoral anatomy such as severe peripheral vascular disease or diffuse circumferential vessel calcification. The degree of aortic valve leaflet and annular calcification also needs to be assessed as the latter is a risk factor for post-procedural paravalvular aortic regurgitation. The ultimate goal of patient selection is to achieve the highest procedural success rate while minimizing complications and to choose patients most likely to derive tangible benefit from this procedure.