Bioprosthetic valve fracture during valve-in-valve transcatheter aortic valve replacement: multicenter propensity matched analysis

Background

Valve-in-valve (ViV) transcatheter aortic valve implantation (TAVI) can be completed by bioprosthetic valve fracture (BVF) to reduce final transvalvular gradients. The aim was to compare outcomes in ViV-TAVI patients with versus without BVF.

Methods

Consecutive patients undergoing ViV-TAVI procedure in four international centers were included, from 2010 to 2021. We used a 1:2 propensity score-matching method to compare postprocedural hemodynamic, complications, and long-term outcomes. Patients were matched for baseline characteristics, time since prior surgery, and characteristics of surgical bioprothesis (type and size).

Results

A total of 390 patients were analyzed, including 40 BVF. Propensity matching 1:2 yielded 38 patients in BVF group and 76 patients in no-BVF group. There was no difference in procedural complications rate and in-hospital deaths (5.1%) between the two groups. Post-procedural hemodynamic parameters significantly improved using BVF: aortic valve area (1.4 cm2 [IQR: 1.23 to 2.3] vs. 1.3 cm2 [IQR: 1.05 to 1.61], p=0.008), mean aortic gradient (12mmHg [IQR: 7.5 to 16.5] vs. 17mmHg [IQR: 11 to 22], p=0.008) and peak velocity (2.2m/s [IQR: 1.8 to 2.7] vs. 2.6m/s [IQR: 2.2 to 3.1], p=0.027). BVF had an additional benefit in the smallest surgical valve (≤21 mm). The use of BVF was independently associated with improved hemodynamic parameters. Overall survival in the matched cohort was 87.8±3.7% at 2-year follow-up, without difference between groups (87.5±6.9% in the BVF group vs. 88.4±4.2% in the no-BVF group, p=0.85).

Conclusion

Compared to ViV-TAVI alone, BVF was safe and improved immediate hemodynamic and long-term outcomes, especially in patients with small surgical aortic bioprosthesis.

Funding Acknowledgement

Type of funding sources: None.

O-159 Uniform communication by nurses and midwives in anticipation of an IVF treatment

Study question

How do patients perceive the pre-IVF treatment communication by the nursing and midwifery team and how do they evaluate implemented optimization?

Summary answer

Patient satisfaction with the pre-IVF treatment communication by the nursing and midwifery team improved from 86% to 98% after implementation of standardized written patient information.

What is known already

Nurses are the main point of contact for patients undergoing medically assisted reproduction techniques (Applegarth et al., 2008). Morris (2001) suggested that infertility nurses could more specifically be involved in informative counselling in anticipation of the fertility treatment. Specific training for nurses and midwives would be required in order to achieve that central role in effective fertility counselling (Applegarth et al., 2012). However, little has been published in peer reviewed literature on how to assess and improve these pre-IVF treatment information sessions.

Study design, size, duration

The pre-IVF communication by the nurse/midwife was assessed by female patients with a self-developed questionnaire (cohort 1). The nursing and midwifery team was subsequently informed about the results of the questionnaire and efforts were undertaken to optimise future patient communication. Four years later, a follow-up questionnaire assessed patient satisfaction about the intervention (cohort 2). Each cohort comprised fifty patients and nurses and midwives were blinded for patient participation to the study.

Participants/materials, setting, methods

The study was performed at an academic fertility centre and was approved by the Investigational Review Board. Data were collected with SurveyMonkey (pre intervention) and REDCap (post intervention). A descriptive analysis of the cohorts and patient feedback was performed. The intervention consisted of (1) the optimization of patient information documents if needed (2) providing a training to the nursing and midwifery staff, and (3) a follow-up questionnaire in a second cohort of female fertility patients.

Main results and the role of chance

The first questionnaire revealed that overall, patients were satisfied with the informative counselling session in anticipation of the IVF treatment. However, some patients indicated that they received a lot of information at once and that specific information that was of relevance for the further treatment (e.g. oocyte pick-up) was sometimes missed. Also, the data showed that not all patients received the same information. Therefore, all information that patients needed during an IVF treatment was gathered into a patient binder. It was supplemented with a timeline of the whole IVF trajectory, QR codes to movies explaining the administration of medication, and answers to common patients’ questions. It was possible to individualize the content of the binder per patient. Ideally, patients received this binder before the informative counselling session so they could read the content in advance. The binder was developed by a member of the nursing and midwifery team and was reviewed by the medical, laboratory, and administrative staff. Then, the nursing and midwifery team was trained on the use of the patient binder. The follow-up questionnaire revealed that patient satisfaction with the pre-IVF treatment counselling was 98% after the optimization of patient documentation (compared to 86% before the optimization).

Limitations, reasons for caution

Eligible patients were recruited by the treating physician. As no records were kept of the number of solicited patients for this study, no assessment of the response rate is possible. The cohorts were self-selected and limited in size and could therefore not reflect the general patient population.

Wider implications of the findings

A patient questionnaire and follow-up is a useful tool for a centre specific assessment and improvement of pre-IVF nurse/midwife communication with patients. Clinics could make efforts to invest in complete and written information and ask colleagues of the nursing and midwifery team to be involved in its creation.

Trial registration number

NCT04420169

P1838Thrombocytopenia under ECMO and Shear-induced shedding of platelet receptor Glycoprotein-(GP)Ialpha

Background

Several mechanisms are suspected to thrombocytopenia under Extracorporeal Membrane Oxygenation (ECMO) such as platelet-consumption or sepsis. Shedding of glycoprotein-(GP)Ibα is a recently identified mechanism of platelet clearance. ECMO generates high shear stress forces that could impact GPIbα-shedding. We hypothesized that ECMO continuous-flow devices could directly induce thrombocytopenia through shear-induced GPIbα-shedding.

Aims

Determine if ECMO induce GpIb-shedding in vitro and in vivo and determinates the kinetic evolution of platelet-count and GpIb-shedding after patient's implantation.

Methods

Platelet GPIbα-shedding was first investigated in vitro using a high-shear pump loop model. Plasma with normal platelet count (plasma-NPC) was obtained by dilution of platelet-rich plasma obtained from healthy donors in fresh-frozen-plasma. Samples were collected before and after (5, 30, 60 and 180 min) perfusion at 37°C of plasma-NPC at intermediate and high speed (2.6 and 3.6 L min–1 respectively, n=4 each). Platelet count and GPIbα-shedding were next investigated in 20 ECMO patients before/after implantation (WITECMO trial) and in 20 healthy volunteers. The geometric mean-fluorescence-intensity (gMFI) of platelet GPIbα (PE-staining) and GPIX (FITC-staining) was measured with a Navios flow cytometer (Beckman Coulter, Miami, FL). Results are expressed as GPIbα/GPIX gMFI-ratio.

Results

A significant time-dependent loss of GPIbα/GPIX gMFI-ratio was already apparent after 30 min in vitro and was significantly more pronounced at high-speed compared to intermediate-speed (pANOVA<0.001 and p<0.01 at 180 min respectively). GPIbα/GPIX gMFI-ratio was significantly increased in ECMO patients compared to healthy subjects 1- and 24-hour after implantation (p<0.001). A significantly lower platelet count was observed 1 hour after ECMO implantation (−23% vs baseline, p<0.01) with a further significant decrease at 24-hours (−53% vs baseline, p<0.0001).

Figure 1. A. Significant time-dependent loss of platelet GPIbα/GPIX gMFI-ratio (pANOVA <0.001) assessed by flow-cytometry after 30 min of perfusion at 3.6 L/min with a high-shear continuous-flow device in vitro. B. Representative experiment showing the apparition of a platelet sub-population with loss of GPIbα expression after 30 min of perfusion at 3.6 L/minwith a high-shear continuous-flow device in vitro.

Circulatory support devices: fundamental aspects and clinical management of bleeding and thrombosis

Circulatory support devices are increasingly being used to overcome cardiac or respiratory failure. Long-term devices are used either as a 'bridge to transplant' to support patients who are unable to wait any longer for a heart transplant, or, more recently, as 'destination therapy' for older patients suffering from end-stage heart failure and who have contraindications to heart transplantation. Short-term support devices for high-risk percutaneous coronary intervention, or as a 'bridge for decision' for patients suffering from refractory cardiogenic shock, have also been developed. The clinical benefit of such assist devices has been demonstrated in several important studies, but, unfortunately, thrombotic and bleeding complications are two major clinical issues in patients requiring these devices. Overcoming these issues is of major importance to allow the safe and broad use of these devices, and to consider them as true alternatives to heart transplantation. The present review focuses on thrombotic and bleeding complications, and describes how the risk of thrombosis and bleeding may vary according to the clinical indication, but also according to the type of device. We describe the current knowledge of the mechanisms underlying the occurrence of these complications, provide some guidance for choosing the most appropriate anticoagulation regimen to prevent their occurrence for each type of device and indication, and provide some recommendations for the management of patients when the complication occurs.

One-year clinical follow-up of a registry evaluating a percutaneous revascularisation strategy combining a pre-specified simple selection process with the use of a new thin-strut bare cobalt-chromium stent

Objectives. To evaluate clinical events in a specifically selected cohort of patients with obstructive coronary artery disease (CAD), using a new generation thin-strut bare cobalt-chromium coronary stent.Methods. Patients with single- or multi-vessel, stable or unstable CAD eligible for percutaneous implantation of at least one bare cobalt-chromium stent were evaluated in a single-centre registry. Prospective pre-specified criteria for bare cobalt-chromium stent implantation in our centre were: any acute ST-elevation myocardial infarction (MI), otherwise 1) de novo coronary lesion, and 2) lesion length <20 mm, and 3) reference vessel diameter >2.6 mm, and 4) no diabetes, unless reference vessel diameter >3.5 mm. Endpoints, retrospectively collected, were death, MI and clinically driven target-lesion revascularisation (TLR) and target-vessel revascularisation (TVR) after 12 months.Results. Between September 2005 and June 2007, 712 patients (48.7% one-vessel, 29.9% two-vessel, 20% three-vessel and 1.4% left main disease; 7.9% diabetics) were treated with 800 bare cobalt-chromium stents, for stable angina (40.9%), unstable angina (20.9%) or acute ST-elevation MI (38.2%). The procedural success rate was 99.3%. Peri-procedural MI rate was 2.2% in the semi-elective group. At 12 months there were 17 deaths (2.4%), of which nine non-cardiac, 20 (2.8%) MI, 19 (2.7%) TLR and 29 (4.1%) TVR. Early and late definite stent thrombosis occurred in four (0.6%) and three (0.4%) patients, respectively.Conclusion. A strategy aimed at minimising drug-eluting stent use and combining a pre-specified simple selection process with the use of a new thin-strut bare cobalt-chromium stent is safe and effective at one-year clinical follow-up. (Neth Heart J 2010;18:486-92.).

Drug-eluting stents: trading restenosis for thrombosis?

Within the last 6 years, it has been demonstrated that drug-eluting stents (DES) reduce significantly angiographic and clinical restenosis after percutaneous coronary interventions. These results are consistent across several clinical randomized controlled trials comparing these new devices with bare metallic stents (BMS), which themselves have already markedly improved the results obtained with balloon angioplasty in the early days of this method of myocardial revascularization. Nevertheless, some concerns have been raised regarding a delayed endothelialization of the coated prostheses leading to late stent thrombosis occurring mainly when antiplatelet therapy is discontinued in the follow-up. The most recent data show that, in comparison with BMS, there is a small excess of late (> 1 year) stent thrombosis but this is not associated with an increased risk of death or myocardial infarction or all cause mortality. These concerns do not outweigh the strong benefits of DES in preventing restenosis but require a number of measures concerning a longer dual antiplatelet treatment (than initially expected), to control patient treatment compliance and to provide a complete education of patients and physicians. Future devices dealing with the two issues (antiproliferative properties with rapid controlled endothelialization preventing thrombosis) would be the next major advance in this rapidly evolving field.

Functional mitral regurgitation and chronic heart failure

Functional mitral regurgitation (MR) frequently develops during the progression of chronic heart failure and predicts poor outcome. Impaired left ventricular (LV) function, LV remodeling associated with papillary muscle apical displacement and annular enlargement result in decreased mitral closing forces and tenting of the mitral valve at closure. Reduced closing forces and tenting both promote MR. Active myocardial ischemia, myocardial asynchronism and excessive loading conditions worsen MR at rest and during exercise. The therapeutic target in functional MR is the left ventricle and not the valve.

Cardiac resynchronisation therapy reduces functional mitral regurgitation during dynamic exercise in patients with chronic heart failure: an acute echocardiographic study

OBJECTIVES

To assess non-invasively the acute effects of cardiac resynchronisation therapy (CRT) on functional mitral regurgitation (MR) at rest and during dynamic exercise.

METHODS

21 patients with left ventricular (LV) systolic dysfunction and functional MR at rest, treated with CRT, were studied. Each patient performed a symptom-limited maximal exercise with continuous two dimensional Doppler echocardiography twice. The first exercise was performed with CRT; the second exercise was performed without CRT. Mitral regurgitant flow volume (RV), effective regurgitant orifice area (ERO) and LV dP/dt were measured at rest and at peak exercise.

RESULTS

CRT mildly reduced resting mitral ERO (mean 8 (SEM 2) v 11 (2) mm(2) without CRT, p = 0.02) and RV (13 (3) v 18 (3) ml without CRT, p = 0.03). CRT attenuated the spontaneous increase in mitral ERO and RV during exercise (1 (1) v 9 (2) mm(2), p = 0.004 and 1 (1) v 8 (2) ml, p = 0.004, respectively). CRT also significantly increased exercise-induced changes in LV dP/dt (140 (46) v 479 (112) mm Hg/s, p < 0.001).

CONCLUSION

Attenuation of functional MR, induced by an increase in LV contractility during dynamic exercise, may contribute to the beneficial clinical outcome of CRT in patients with chronic heart failure and LV asynchrony.

[Does diabetes affect therapy in coronary patients? Revascularisation]

Techniques of myocardial revascularisation are very commonly employed in diabetic patients. In unstable angina, the reported data suggests a very significant benefit of an invasive strategy for the diabetic patient. In stable angina, subgroups analysis of randomised clinical trials carried out over ten years ago showed a better outcome after surgery in cases of multivessel disease. What has been the impact of technical advances archived since then? Active stents and antiplatelet drugs have considerably improved the outcome of diabetics treated by angioplasty. Cardiac surgery has also made considerable progress with the systematic use of arterial grafts. New randomised clinical trials are underway to determine the modern options of myocardial revascularisation for diabetic patients.

[The use of the RESCUE thromboaspiration system in acute coronary syndrome]

Interventional procedures associated with acute coronary syndromes or performed on saphenous bypass grafts frequently lead to embolic complications, resulting in no-reflow phenomenon, side-branch occlusion, or peri-procedural infarction. The RESCUE thrombo-aspiration system was used in 19 percutaneous coronary interventions. After initial use of the aspiration device, 81% of procedures were followed by stent deployment. TIMI flow 2 or higher was present in 42% at the beginning of the procedure and in 95% at the end. In-hospital MACE rate was 4.76%. This relatively user-friendly technique appears rapid and efficacious in the case of visible intracoronary thrombus.

[Restenosis and vascular response after angioplasty: physiopathological data]

Our purpose is to review the different mechanisms involved in the vascular response following percutaneous coronary revascularization, and their role in thrombotic complications and in restenosis. Specificities related to the various techniques of percutaneous coronary revascularization (balloon angioplasty, coronary stents, brachytherapy, drug eluting stents) are discussed.

[Coronary thrombosis imaging in humans]

The identification of coronary thrombosis in humans has important prognostic and therapeutic implications. Its recognition calls for invasive techniques: angioscopy, coronarography, and endocoronary ultrasound. Angioscopy allows visualisation of the arterial surface and the detection of thrombus with great sensitivity. Its presence is exclusive to the acute coronary syndromes: 67% in unstable angina, and 75% in myocardial infarction, although it is only present in 27% of cases of stable angina. The relative complexity of its use has led to the abandonment of this technique. Coronarography allows an indirect approach to coronary thrombosis. Certain aspects are evocative such as: intraluminal filling defect, complete occlusion with upstream convexity, ulceration and eccentric type 2 Ambrose classification plaques. As a function of the clinical presentation, the coronarographic views allow a good specificity for the diagnosis of thrombus. The sensitivity is weak, however, compared to angioscopy. Endocoronary ultrasound does not allow identification of fresh thrombus which is not echogenic and does not allow differentiation between older thrombus and lipid plaque. In the future, magnetic resonance imaging could prove interesting in the detection of recent thrombus.

Patency of percutaneous transluminal coronary angioplasty sites at 6-month angiographic follow-up: A key determinant of survival in diabetics after coronary balloon angioplasty

BACKGROUND

Several reports have demonstrated a high mortality rate in diabetic patients treated by standard coronary balloon angioplasty. No clear explanation has been provided for this finding.

METHODS AND RESULTS

Consecutive diabetic patients successfully treated by standard coronary balloon angioplasty (n=604) were enrolled in a follow-up program including repeated angiography at 6 months and long-term clinical follow-up. Clinical follow-up was available in 603 patients (99.8%). Twelve patients died, 2 underwent bypass surgery before scheduled repeated angiography, and 76 declined angiography. Determinants of long-term mortality were analyzed in the 513 patients with angiography at 6 months and long-term clinical follow-up (mean follow-up, 6.5+/-2.4 years). On the basis of the results of repeated angiography, 3 groups of patients were defined: group 1, 162 patients without restenosis (32%); group 2, 257 patients with nonocclusive restenosis (50%); and group 3, 94 patients with coronary occlusion (18%). Overall actuarial 10-year mortality rate was 36%. Actuarial 10-year mortality was 24% in group 1, 35% in group 2, and 59% in group 3 (P:<0.0001). Multivariate analysis demonstrated that coronary occlusion was a strong and independent correlate of long-term total mortality (hazard ratio, 2.16; 95% CI, 1.43 to 3.26; P:=0.0003) and cardiac mortality (hazard ratio, 2.38; 95% CI, 1.48 to 3.85; P:=0.0004).

CONCLUSIONS

This study demonstrates that restenosis, especially in its occlusive form, is a major determinant of long-term mortality in diabetic patients after coronary balloon angioplasty.

Effect of percutaneous adenovirus-mediated Gax gene delivery to the arterial wall in double-injured atheromatous stented rabbit iliac arteries

Though the efficacy of intravascular gene transfer has been demonstrated in native vessels following acute injury, this methodology has not been validated in complex models of vascular injury that more closely mimic clinical angioplasty procedures. Previous studies have shown that Gax gene overexpression modulates the injury-induced remodeling of the vessel in rat carotid and normal rabbit iliac arteries. Here, we evaluated the effect of the Gax gene delivery in atheromatous stented vessels. Rabbits were fed 120 g daily of 1% cholesterol diet for 3 weeks. At 1 week they underwent initial injury on the external iliac artery, then balloon angioplasty was performed at 3 weeks at the same site with a 2.5 mm diameter channel balloon catheter (three times 1 min at 6 atm). Either saline (n = 4) or the control viral construct Ad-CMVluc (5 x 109 p.f.u.) (n = 5) or Ad-CMVGax (5 x 10(9) p.f.u.) (n = 4) was delivered with a poloxamer mixture via a channel balloon (6 atm, 30 min), and a 15 mm long Palmaz-Schatz stent (PS154) was then deployed at the site (1 min, 8 atm). Arteries were analyzed 1 month later. At 1 month, the Ad-CMVGax treated arteries exhibited a lower maximal intimal area (1. 15+/-0.1 mm2) than saline (1.87+/-0.15 mm2, P = 0.007) or Ad-CMVluc-treated vessels (1.98+/-0.31 mm2, P = 0.04). Likewise Ad-CMVGax-treated vessels displayed a lower maximal percentage cross-sectional area narrowing (35.1+/-3.5%) than saline (65.3+/-9.4%, P = 0.01) or Ad-CMVluc-treated vessels (62.7+/-6.7%, P = 0.02). Angiographic analysis revealed larger minimal lumen diameter in Ad-CMVGax treated arteries (2.0+/-0.1 mm) than saline (1.14+/-0.36 mm, P = 0.06) or Ad-CMVluc-treated vessels (1.23+/-0.25 mm, P = 0.02). Overexpression of the Gax gene inhibits neointimal hyperplasia and lumen loss in atheromatous stented rabbit iliac arteries.

A comparison of systematic stenting and conventional balloon angioplasty during primary percutaneous transluminal coronary angioplasty for acute myocardial infarction. STENTIM-2 Investigators

OBJECTIVES

In a multicenter, randomized trial, systematic stenting using the Wiktor stent was compared to conventional balloon angioplasty with provisional stenting for the treatment of acute myocardial infarction (AMI).

BACKGROUND

Primary angioplasty in AMI is limited by in-hospital recurrent ischemia and a high restenosis rate.

METHODS

A total of 211 patients with AMI <12 h from symptom onset, with an occluded native coronary artery, were randomly assigned to systematic stenting (n = 101) or balloon angioplasty (n = 110). The primary end point was the binary six-month restenosis rate determined by core laboratory quantitative angiographic analysis.

RESULTS

Angiographic success (Thrombolysis in Myocardial Infarction [TIMI] flow grade 3 and residual diameter stenosis <50%) was achieved in 86% of the patients in the stent group and in 82.7% of those in the balloon angioplasty group (p = 0.5). Compared with the 3% cross-over in the stent group, cross-over to stenting was required in 36.4% of patients in the balloon angioplasty group (p = 0.0001). Six-month binary restenosis (> or = 50% residual stenosis) rates were 25.3% in the stent group and 39.6% in the balloon angioplasty group (p = 0.04). At six months, the event-free survival rates were 81.2% in the stent group and 72.7% in the balloon angioplasty group (p = 0.14), and the repeat revascularization rates were 16.8% and 26.4%, respectively (p = 0.1). At one year, the event-free survival rates were 80.2% in the stent group and 71.8% in the balloon angioplasty group (p = 0.16), and the repeat revascularization rates were 17.8% and 28.2%, respectively (p = 0.1).

CONCLUSIONS

In the setting of primary angioplasty for AMI, as compared with a strategy of conventional balloon angioplasty, systematic stenting using the Wiktor stent results in lower rates of angiographic restenosis.