A review of transgenic animal techniques and their applications

Nowadays, breakthroughs in molecular biology are happening at an unprecedented rate. One of them is the ability to engineer transgenic animals. A transgenic animal is one whose genome has been changed to carry genes from another species or to use techniques for animal genome editing for specific traits. Animal features can be changed by purposefully altering the gene (or genes). A mouse was the first successful transgenic animal. Then pigs, sheep, cattle, and rabbits came a few years later. The foreign-interested genes that will be used in animal transgenic techniques are prepared using a variety of methods. The produced gene of interest is placed into a variety of vectors, including yeast artificial chromosomes, bacterial plasmids, and cosmids. Several techniques, including heat shock, electroporation, viruses, the gene gun, microinjection, and liposomes, are used to deliver the created vector, which includes the interesting gene, into the host cell. Transgenesis can be carried out in the gonads, sperm, fertilized eggs, and embryos through DNA microinjection, retroviruses, stem cells, and cloning. The most effective transgenic marker at the moment is fluorescent protein. Although transgenesis raises a number of ethical concerns, this review concentrates on the fundamentals of animal transgenesis and its usage in industry, medicine, and agriculture. Transgenesis success is confirmed by the integration of an antibiotic resistance gene, western and southern blots, PCR, and ELISA. If technology solves social and ethical problems, it will be the most promising in the future.

Transcatheter Tricuspid Valve Intervention in Patients With Right Ventricular Dysfunction or Pulmonary Hypertension: Insights From the TriValve Registry

BACKGROUND

Scarce data exist on patients with right ventricular dysfunction (RVD) or pulmonary hypertension (PH) undergoing transcatheter tricuspid valve intervention. This study aimed to determine the early and midterm outcomes and the factors associated with mortality in this group of patients.

METHODS

This subanalysis of the multicenter TriValve (Transcatheter Tricuspid Valve Therapies) registry included 300 patients with severe tricuspid regurgitation with RVD (n=244), PH (n=127), or both (n=71) undergoing transcatheter tricuspid valve intervention. RVD was defined as a tricuspid annular plane systolic excursion <17 mm, and PH as an estimated pulmonary artery systolic pressure ≥50 mm Hg.

RESULTS

Mean age of the patients was 77±9 years (54% women). Procedural success was 80.7%, and 9 patients (3%) died during the hospitalization. At a median follow-up of 6 (interquartile range, 2-12) months, 54 patients (18%) died, and the independent associated factors were higher gamma-glutamyl transferase values at baseline (hazard ratio, 1.02 for each increase of 10 u/L [95% CI, 1.002-1.04]), poorer renal function defined as an estimated glomerular filtration rate <45 mL/min (hazard ratio, 2.3 [95% CI, 1.22-4.33]), and the lack of procedural success (hazard ratio, 2.11 [95% CI, 1.17-3.81]). The grade of RVD and the amount of PH at baseline were not found to be predictors of mortality. Most patients alive at follow-up improved their functional class (New York Heart Association I-II in 66% versus 7% at baseline, P<0.001).

CONCLUSIONS

In patients with severe tricuspid regurgitation and RVD/PH, transcatheter tricuspid valve intervention was associated with high procedural success and a relatively low in-hospital mortality, along with significant improvements in functional status. However, about 1 out of 5 patients died after a median follow-up of 6 months, with hepatic congestion, renal dysfunction, and the lack of procedural success determining an increased risk. These results may improve the clinical evaluation of transcatheter tricuspid valve intervention candidates and would suggest a closer follow-up in those at increased risk. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT03416166.

Outcomes of TTVI in Patients With Pacemaker or Defibrillator Leads: Data From the TriValve Registry

OBJECTIVES

The interference of a transtricuspid cardiac implantable electronic device (CIED) lead with tricuspid valve function may contribute to the mechanism of tricuspid regurgitation (TR) and poses specific therapeutic challenges during transcatheter tricuspid valve intervention (TTVI). Feasibility and efficacy of TTVI in presence of a CIED is unclear.

BACKGROUND

Feasibility of TTVI in presence of a CIED lead has never been proven on a large basis.

METHODS

The study population consisted of 470 patients with severe symptomatic TR from the TriValve (Transcatheter Tricuspid Valve Therapies) registry who underwent TTVI at 21 centers between 2015 and 2018. The association of CIED and outcomes were assessed.

RESULTS

Pre-procedural CIED was present in 121 of 470 (25.7%) patients. The most frequent location of the CIED lead was the posteroseptal commissure (44.0%). As compared with patients without a transvalvular lead (no-CIED group), patients having a tricuspid lead (CIED group) were more symptomatic (New York Heart Association functional class III to IV in 95.9% vs. 92.3%; p = 0.02) and more frequently had previous episodes of right heart failure (87.8% vs. 69.0%; p = 0.002). No-CIED patients had more severe TR (effective regurgitant orifice area 0.7 ± 0.6 cm² vs. 0.6 ± 0.3 cm²; p = 0.02), but significantly better right ventricular function (tricuspid annular plane systolic excursion = 16.7 ± 5.0 mm vs. 15.9 ± 4.0 mm; p = 0.04). Overall, 373 patients (79%) were treated with the MitraClip (Abbott Vascular, Santa Clara, California) (106 [87.0%] in the CIED group). Among them, 154 (33%) patients had concomitant transcatheter mitral repair (55 [46.0%] in the CIED group, all MitraClip). Procedural success was achieved in 80.0% of no-CIED patients and in 78.6% of CIED patients (p = 0.74), with an in-hospital mortality of 2.9% and 3.7%, respectively (p = 0.70). At 30 days, residual TR ≤2+ was observed in 70.8% of no-CIED and in 73.7% of CIED patients (p = 0.6). Symptomatic improvement was observed in both groups (NYHA functional class I to II at 30 days: 66.0% vs. 65.0%; p = 0.30). Survival at 12 months was 80.7 ± 3.0% in the no-CIED patients and 73.6 ± 5.0% in the CIED patients (p = 0.30).

CONCLUSIONS

TTVI is feasible in selected patients with CIED leads and acute procedural success and short-term clinical outcomes are comparable to those observed in patients without a transtricuspid lead.

Ultra-hydrophilic stent platforms promote early vascular healing and minimise late tissue response: a potential alternative to second-generation drug-eluting stents

AIMS

Simple surface modifications can enhance coronary stent performance. Ultra-hydrophilic surface (UHS) treatment of contemporary bare metal stents (BMS) was assessed in vivo to verify whether such stents can provide long-term efficacy comparable to second-generation drug-eluting stents (DES) while promoting healing comparably to BMS.

METHODS AND RESULTS

UHS-treated BMS, untreated BMS and corresponding DES were tested for three commercial platforms. A thirty-day and a 90-day porcine coronary model were used to characterise late tissue response. Three-day porcine coronary and seven-day rabbit iliac models were used for early healing assessment. In porcine coronary arteries, hydrophilic treatment reduced intimal hyperplasia relative to the BMS and corresponding DES platforms (1.5-fold to threefold reduction in 30-day angiographic and histological stenosis; p<0.04). Endothelialisation was similar on UHS-treated BMS and untreated BMS, both in swine and rabbit models, and lower on DES. Elevation in thrombotic indices was infrequent (never observed with UHS, rare with BMS, most often with DES), but, when present, correlated with reduced endothelialisation (p<0.01).

CONCLUSIONS

Ultra-hydrophilic surface treatment of contemporary stents conferred good healing while moderating neointimal and thrombotic responses. Such surfaces may offer safe alternatives to DES, particularly when rapid healing and short dual antiplatelet therapy (DAPT) are crucial.

Synthesis and characterization of nanosilver-silicone hydrogel composites for inhibition of bacteria growth

PURPOSE

Nanosilver-silicone hydrogel (NAgSiH) composites for contact lenses were synthesized to asses the antimicrobial effects.

METHODS

Silicone hydrogel (SiH) films were synthesized followed by impregnation in silver nitrate solutions (10, 20, 30, 40, 60, 80ppm) and in-situ chemical reduction of silver ions using sodium borohydride (NaBH₄). The silver nano particles (AgNPS) were identified by UV-vis absorption spectroscopy, Energy-dispersive X-ray spectroscopy (EDX) mapping and EDX spectrum. Physico-mechanical and chemical properties of NAgSIH films were studied. The antimicrobial effect of the hydrogels against Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis and Staphylococcus aureus was evaluated. The numbers of viable bacterial cells on NAgSiH surface or in solution compared to control SiH were examined.

RESULTS

The NAgSiH films were successfully synthesized. FTIR results indicated that AgNPS had no effect on the bulk structure of the prepared SiH films. From TGA analysis, NAgSiH(R80) and SiH(R0) films had the same maximum decomposition temperature (404°C). UV-vis absorption spectroscopy and EDX mapping and spectrum emphasized that AgNPS were in spherical shape. The maximum absorption wavelength of NAgSiH films were around 400nm. The light transmittance decreased as the concentration of AgNPS increased, but still greater than 90% at wavelength around 555nm. The Young's modulus increased gradually from 1.06MPa of SiH(R0) to highest value 1.38MPa of NAgSiH(R80). AgNPS incorporated into SiH films reduced the bacterial cell growth and prevented colonization. Groups NAgSiH(R60,R80) demonstrated an excellent reduction in bacterial viability in solution and on the SiH surface.

CONCLUSIONS

NAgSiH composites were successfully synthesized and possessed an excellent antimicrobial effects.

Effect of Pulmonary Hypertension Hemodynamic Presentation on Clinical Outcomes in Patients With Severe Symptomatic Aortic Valve Stenosis Undergoing Transcatheter Aortic Valve Implantation: Insights From the New Proposed Pulmonary Hypertension Classification

BACKGROUND

Pulmonary hypertension (PH) frequently coexists with severe aortic stenosis, and PH severity has been shown to predict outcomes after transcatheter aortic valve implantation (TAVI). The effect of PH hemodynamic presentation on clinical outcomes after TAVI is unknown.

METHODS AND RESULTS

Of 606 consecutive patients undergoing TAVI, 433 (71.4%) patients with severe aortic stenosis and a preprocedural right heart catheterization were assessed. Patients were dichotomized according to whether PH was present (mean pulmonary artery pressure, ≥25 mm Hg; n=325) or not (n=108). Patients with PH were further dichotomized by left ventricular end-diastolic pressure into postcapillary (left ventricular end-diastolic pressure, >15 mm Hg; n=269) and precapillary groups (left ventricular end-diastolic pressure, ≤15 mm Hg; n=56). Finally, patients with postcapillary PH were divided into isolated (n=220) and combined (n=49) subgroups according to whether the diastolic pressure difference (diastolic pulmonary artery pressure-left ventricular end-diastolic pressure) was normal (<7 mm Hg) or elevated (≥7 mm Hg). Primary end point was mortality at 1 year. PH was present in 325 of 433 (75%) patients and was predominantly postcapillary (n=269/325; 82%). Compared with baseline, systolic pulmonary artery pressure immediately improved after TAVI in patients with postcapillary combined (57.8±14.1 versus 50.4±17.3 mm Hg; P=0.015) but not in those with precapillary (49.0±12.6 versus 51.6±14.3; P=0.36). When compared with no PH, a higher 1-year mortality rate was observed in both precapillary (hazard ratio, 2.30; 95% confidence interval, 1.02-5.22; P=0.046) and combined (hazard ratio, 3.15; 95% confidence interval, 1.43-6.93; P=0.004) but not isolated PH patients (P=0.11). After adjustment, combined PH remained a strong predictor of 1-year mortality after TAVI (hazard ratio, 3.28; P=0.005).

CONCLUSIONS

Invasive stratification of PH according to hemodynamic presentation predicts acute response to treatment and 1-year mortality after TAVI.

Clinical outcomes and revascularization strategies in patients with low-flow, low-gradient severe aortic valve stenosis according to the assigned treatment modality

OBJECTIVES

This study compared clinical outcomes and revascularization strategies among patients presenting with low ejection fraction, low-gradient (LEF-LG) severe aortic stenosis (AS) according to the assigned treatment modality.

BACKGROUND

The optimal treatment modality for patients with LEF-LG severe AS and concomitant coronary artery disease (CAD) requiring revascularization is unknown.

METHODS

Of 1,551 patients, 204 with LEF-LG severe AS (aortic valve area <1.0 cm(2), ejection fraction <50%, and mean gradient <40 mm Hg) were allocated to medical therapy (MT) (n = 44), surgical aortic valve replacement (SAVR) (n = 52), or transcatheter aortic valve replacement (TAVR) (n = 108). CAD complexity was assessed using the SYNTAX score (SS) in 187 of 204 patients (92%). The primary endpoint was mortality at 1 year.

RESULTS

LEF-LG severe AS patients undergoing SAVR were more likely to undergo complete revascularization (17 of 52, 35%) compared with TAVR (8 of 108, 8%) and MT (0 of 44, 0%) patients (p < 0.001). Compared with MT, both SAVR (adjusted hazard ratio [adj HR]: 0.16; 95% confidence interval [CI]: 0.07 to 0.38; p < 0.001) and TAVR (adj HR: 0.30; 95% CI: 0.18 to 0.52; p < 0.001) improved survival at 1 year. In TAVR and SAVR patients, CAD severity was associated with higher rates of cardiovascular death (no CAD: 12.2% vs. low SS [0 to 22], 15.3% vs. high SS [>22], 31.5%; p = 0.037) at 1 year. Compared with no CAD/complete revascularization, TAVR and SAVR patients undergoing incomplete revascularization had significantly higher 1-year cardiovascular death rates (adj HR: 2.80; 95% CI: 1.07 to 7.36; p = 0.037).

CONCLUSIONS

Among LEF-LG severe AS patients, SAVR and TAVR improved survival compared with MT. CAD severity was associated with worse outcomes and incomplete revascularization predicted 1-year cardiovascular mortality among TAVR and SAVR patients.

Rotational atherectomy before paclitaxel-eluting stent implantation in complex calcified coronary lesions: Two-year clinical outcome of the randomized ROTAXUS trial

BACKGROUND

In the randomized ROTAXUS trial, routine lesion preparation of complex calcified coronary lesions using rotational atherectomy (RA) prior to paclitaxel-eluting stent implantation did not reduce the primary endpoint of angiographic late lumen loss at 9 months compared to stenting without RA. So far, no long-term data of prospective head-to-head comparisons between both treatment strategies have been reported.

METHODS AND RESULTS

ROTAXUS randomly assigned patients with complex calcified coronary lesions to RA followed by stenting (n = 120) or stenting without RA (n = 120). The primary endpoint of the current analysis was the occurrence of major adverse cardiac events (MACE) at 2-year follow-up defined as the composite of death, myocardial infarction, and target vessel revascularization (TVR). At 2 years, MACE occurred in 32 patients in the RA group and 37 patients in the standard therapy group (29.4% vs. 34.3%, P = 0.47). The rates of death (8.3% vs. 7.4%, P = 1.00), myocardial infarction (8.3% vs. 6.5%, P = 0.80), target lesion revascularization (TLR, 13.8% vs. 16.7%, P = 0.58), and TVR (19.3% vs. 22.2%, P = 0.62) were similar in both groups.

CONCLUSION

Despite high rates of initial angiographic success, nearly one third of patients enrolled in ROTAXUS experienced MACE within 2-year follow-up, with no differences between patients treated with or without RA.

Validation of the Valve Academic Research Consortium Bleeding Definition in Patients With Severe Aortic Stenosis Undergoing Transcatheter Aortic Valve Implantation

Background

The Valve Academic Research Consortium (VARC) has proposed a standardized definition of bleeding in patients undergoing transcatheter aortic valve interventions (TAVI). The VARC bleeding definition has not been validated or compared to other established bleeding definitions so far. Thus, we aimed to investigate the impact of bleeding and compare the predictivity of VARC bleeding events with established bleeding definitions.

Methods and Results

Between August 2007 and April 2012, 489 consecutive patients with severe aortic stenosis were included into the Bern‐TAVI‐Registry. Every bleeding complication was adjudicated according to the definitions of VARC, BARC, TIMI, and GUSTO. Periprocedural blood loss was added to the definition of VARC, providing a modified VARC definition. A total of 152 bleeding events were observed during the index hospitalization. Bleeding severity according to VARC was associated with a gradual increase in mortality, which was comparable to the BARC, TIMI, GUSTO, and the modified VARC classifications. The predictive precision of a multivariable model for mortality at 30 days was significantly improved by adding the most serious bleeding of VARC (area under the curve [AUC], 0.773; 95% confidence interval [CI], 0.706 to 0.839), BARC (AUC, 0.776; 95% CI, 0.694 to 0.857), TIMI (AUC, 0.768; 95% CI, 0.692 to 0.844), and GUSTO (AUC, 0.791; 95% CI, 0.714 to 0.869), with the modified VARC definition resulting in the best predictivity (AUC, 0.814; 95% CI, 0.759 to 0.870).

Conclusions

The VARC bleeding definition offers a severity stratification that is associated with a gradual increase in mortality and prognostic information comparable to established bleeding definitions. Adding the information of periprocedural blood loss to VARC may increase the sensitivity and the predictive power of this classification.

Impact of mitral regurgitation on clinical outcomes of patients with low-ejection fraction, low-gradient severe aortic stenosis undergoing transcatheter aortic valve implantation

BACKGROUND

Up to 1 in 6 patients undergoing transcatheter aortic valve implantation (TAVI) present with low-ejection fraction, low-gradient (LEF-LG) severe aortic stenosis and concomitant relevant mitral regurgitation (MR) is present in 30% to 55% of these patients. The effect of MR on clinical outcomes of LEF-LG patients undergoing TAVI is unknown.

METHODS AND RESULTS

Of 606 consecutive patients undergoing TAVI, 113 (18.7%) patients with LEF-LG severe aortic stenosis (mean gradient ≤40 mm Hg, aortic valve area <1.0 cm(2), left ventricular ejection fraction <50%) were analyzed. LEF-LG patients were dichotomized into ≤mild MR (n=52) and ≥moderate MR (n=61). Primary end point was all-cause mortality at 1 year. No differences in mortality were observed at 30 days (P=0.76). At 1 year, LEF-LG patients with ≥moderate MR had an adjusted 3-fold higher rate of all-cause mortality (11.5% versus 38.1%; adjusted hazard ratio, 3.27 [95% confidence interval, 1.31-8.15]; P=0.011), as compared with LEF-LG patients with ≤mild MR. Mortality was mainly driven by cardiac death (adjusted hazard ratio, 4.62; P=0.005). As compared with LEF-LG patients with ≥moderate MR assigned to medical therapy, LEF-LG patients with ≥moderate MR undergoing TAVI had significantly lower all-cause mortality (hazard ratio, 0.38; 95% confidence interval, 0.019-0.75) at 1 year.

CONCLUSIONS

Moderate or severe MR is a strong independent predictor of late mortality in LEF-LG patients undergoing TAVI. However, LEF-LG patients assigned to medical therapy have a dismal prognosis independent of MR severity suggesting that TAVI should not be withheld from symptomatic patients with LEF-LG severe aortic stenosis even in the presence of moderate or severe MR.

Clinical Impact of Gastrointestinal Bleeding in Patients Undergoing Percutaneous Coronary Interventions

Background—

The risk factors and clinical sequelae of gastrointestinal bleeding (GIB) in the current era of drug-eluting stents, prolonged dual antiplatelet therapy, and potent P2Y 12 inhibitors are not well established. We determined the frequency, predictors, and clinical impact of GIB after percutaneous coronary interventions (PCIs) in a contemporary cohort of consecutive patients treated with unrestricted use of drug-eluting stents.

Methods and Results—

Between 2009 and 2012, all consecutive patients undergoing PCI were prospectively included in the Bern PCI Registry. Bleeding Academic Research Consortium (BARC) GIB and cardiovascular outcomes were recorded within 1 year of follow-up. Among 6212 patients, 84.1% received new-generation drug-eluting stents and 19.5% received prasugrel. At 1 year, GIB had occurred in 65 patients (1.04%); 70.8% of all events and 84.4% of BARC ≥3B events were recorded >30 days after PCI. The majority of events (64.4%) were related to upper GIB with a more delayed time course compared with lower GIB. Increasing age, previous GIB, history of malignancy, smoking, and triple antithrombotic therapy (ie, oral anticoagulation plus dual antiplatelet therapy) were independent predictors of GIB in multivariable analysis. GIB was associated with increased all-cause mortality (adjusted hazard ratio, 3.40; 95% confidence interval, 1.67–6.92; P =0.001) and the composite of death, myocardial infarction, or stroke (adjusted hazard ratio, 3.75; 95% confidence interval, 1.99–7.07; P <0.001) and was an independent predictor of all-cause mortality during 1 year.

Conclusions—

Among unselected patients undergoing PCI, GIB has a profound effect on prognosis. Triple antithrombotic therapy emerged as the single drug-related predictor of GIB in addition to patient-related risk factors within 1 year of PCI.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifier: NCT02241291.

Early results of first versus second generation Amplatzer occluders for left atrial appendage closure in patients with atrial fibrillation

BACKGROUND

Transcatheter left atrial appendage (LAA) occlusion has been proven to be an effective treatment for stroke prophylaxis in patients with atrial fibrillation. For this purpose, the Amplatzer cardiac plug (ACP) was introduced. Its second generation, the Amulet, was developed for easier delivery, better coverage, and reduction of complications.

AIM

To investigate the safety and efficacy of first generation versus second generation Amplatzer occluders for LAA occlusion.

METHODS

Retrospective analysis of prospectively collected data from the LAA occlusion registries of the Bern and Zurich university hospitals. Comparison of the last consecutive 50 ACP cases versus the first consecutive 50 Amulet cases in patients with non-valvular atrial fibrillation. For safety, a periprocedural combined endpoint, which is composed of death, stroke, cardiac tamponade, and bailout by surgery was predefined. For efficacy, the endpoint was procedural success.

RESULTS

There were no differences between the two groups in baseline characteristics. The percentage of associated interventions during LAA occlusion was high in (78% with ACP vs. 70% with Amulet p = ns). Procedural success was similar in both groups (98 vs. 94%, p = 0.61). The combined safety endpoint for severe adverse events was reached by a similar rate of patients in both groups (6 vs. 8%, p = 0.7). Overall complication rate was insignificantly higher in the ACP group, which was mainly driven by clinically irrelevant pericardial effusions (24 vs. 14%, p = 0.31). Death, stroke, or tamponade were similar between the groups (0 vs. 2%, 0 vs. 0%, or 6 vs. 6%, p = ns).

CONCLUSION

Transcatheter LAA occlusion for stroke prophylaxis in patients with atrial fibrillation can be performed with similarly high success rates with first and second generations of Amplatzer occluders. According to this early experience, the Amulet has failed to improve results of LAA occlusion. The risk for major procedural adverse events is acceptable but has to be taken into account when selecting patients for LAA occlusion, a preventive procedure.

Feasibility and outcomes of combined transcatheter aortic valve replacement with other structural heart interventions in a single session: a matched cohort study

Background

Concurrent cardiac diseases are frequent among elderly patients and invite simultaneous treatment to ensure an overall favourable patient outcome.

Aim

To investigate the feasibility of combined single-session percutaneous cardiac interventions in the era of transcatheter aortic valve implantation (TAVI).

Methods

This prospective, case–control study included 10 consecutive patients treated with TAVI, left atrial appendage occlusion and percutaneous coronary interventions. Some in addition had patent foramen ovale or atrial septal defect closure in the same session. The patients were matched in a 1:10 manner with TAVI-only cases treated within the same time period at the same institution regarding their baseline factors. The outcome was validated according to the Valve Academic Research Consortium (VARC) criteria.

Results

Procedural time (126±42 vs 83±40 min, p=0.0016), radiation time (34±8 vs 22±12 min, p=0.0001) and contrast dye (397±89 vs 250±105 mL, p<0.0001) were higher in the combined intervention group than in the TAVI-only group. Despite these drawbacks, no difference in the VARC endpoints was evident during the in-hospital period and after 30 days (VARC combined safety endpoint 32% for TAVI only and 20% for combined intervention, p=1.0).

Conclusions

Transcatheter treatment of combined cardiac diseases is feasible even in a single session in a high-volume centre with experienced operators.

Impact of stent overlap on long-term clinical outcomes in patients treated with newer-generation drug-eluting stents

AIMS

Early-generation drug-eluting stent (DES) overlap (OL) is associated with impaired long-term clinical outcomes whereas the impact of OL with newer-generation DES is unknown. Our aim was to assess the impact of OL on long-term clinical outcomes among patients treated with newer-generation DES.

METHODS AND RESULTS

We analysed the three-year clinical outcomes of 3,133 patients included in a prospective DES registry according to stent type (sirolimus-eluting stents [SES; N=1,532] versus everolimus-eluting stents [EES; N=1,601]), and the presence or absence of OL. The primary outcome was a composite of death, myocardial infarction (MI), and target vessel revascularisation (TVR). The primary endpoint was more common in patients with OL (25.1%) than in those with multiple DES without OL (20.8%, adj HR=1.46, 95% CI: 1.03-2.09) and patients with a single DES (18.8%, adj HR=1.74, 95% CI: 1.34-2.25, p<0.001) at three years. A stratified analysis by stent type showed a higher risk of the primary outcome in SES with OL (28.7%) compared to other SES groups (without OL: 22.6%, p=0.04; single DES: 17.6%, p<0.001), but not between EES with OL (22.3%) and other EES groups (without OL: 18.5%, p=0.30; single DES: 20.4%, p=0.20).

CONCLUSIONS

DES overlap is associated with impaired clinical outcomes during long-term follow-up. Compared with SES, EES provide similar clinical outcomes irrespective of DES overlap status.

Coronary artery disease severity and aortic stenosis: clinical outcomes according to SYNTAX score in patients undergoing transcatheter aortic valve implantation

AIM

The aim of this study was to evaluate whether coronary artery disease (CAD) severity exerts a gradient of risk in patients with aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI).

METHODS AND RESULTS

A total of 445 patients with severe AS undergoing TAVI were included into a prospective registry between 2007 and 2012. The preoperative SYNTAX score (SS) was determined from baseline coronary angiograms. In case of revascularization prior to TAVI, residual SS (rSS) was also determined. Clinical outcomes were compared between patients without CAD (n = 158), patients with low SS (0-22, n = 207), and patients with high SS (SS > 22, n = 80). The pre-specified primary endpoint was the composite of cardiovascular death, stroke, or myocardial infarction (MI). At 1 year, CAD severity was associated with higher rates of the primary endpoint (no CAD: 12.5%, low SS: 16.1%, high SS: 29.6%; P = 0.016). This was driven by differences in cardiovascular mortality (no CAD: 8.6%, low SS: 13.6%, high SS: 20.4%; P = 0.029), whereas the risk of stroke (no CAD: 5.1%, low SS: 3.3%, high SS: 6.7%; P = 0.79) and MI (no CAD: 1.5%, low SS: 1.1%, high SS: 4.0%; P = 0.54) was similar across the three groups. Patients with high SS received less complete revascularization as indicated by a higher rSS (21.2 ± 12.0 vs. 4.0 ± 4.4, P < 0.001) compared with patients with low SS. High rSS tertile (> 14) was associated with higher rates of the primary endpoint at 1 year (no CAD:12.5%, low rSS: 16.5%, high rSS: 26.3%, P = 0.043).

CONCLUSIONS

Severity of CAD appears to be associated with impaired clinical outcomes at 1 year after TAVI. Patients with SS > 22 receive less complete revascularization and have a higher risk of cardiovascular death, stroke, or MI than patients without CAD or low SS.

Microemboli in aortic valve replacement

Microembolic signals (MES) can be detected in many recipients of mechanical aortic valve prostheses by transcranial Doppler ultrasound. The nature and etiology of these MES have remained unclear for a long time. The solid and gaseous nature of MES are discussed, as well as whether or not MES may reflect artifacts. Recently, the gaseous nature of these MES has been widely established. To understand the physics of bubble formation related to mechanical heart valve prostheses, it is necessary to discuss the different types of cavitation occurring at the prostheses and the conditions leading to the degassing of blood. We describe the history of transcranial Doppler ultrasound-techniques and the current techniques in the measurement of these signals. Furthermore, the possible clinical impact of MES, as well as strategies for the design of new prostheses and surgical alternatives to diminish their load are discussed.

New approach to direct stenting using a novel "all-in-one" coronary stent system via 5 French diagnostic catheters: a pilot study

OBJECTIVES

We sought to evaluate the strategy success and short term clinical outcomes of direct stenting via 5 French (F) diagnostic catheters using a novel bare metal stent with integrated delivery system (IDS) (Svelte Medical Systems, New Providence, NJ) and compare the results to a conventionally treated matched group.

METHODS

Fifteen consecutive patients with lesions deemed suitable for direct stenting using a bare metal stent were included. The primary endpoint was the strategy success defined as the ability to successfully treat a target lesion via a 5 F diagnostic catheter with a good angiographic result (TIMI III flow, residual stenosis ≤20%). Procedure and fluoroscopy times, contrast agent use, cost, and short-term clinical outcomes were compared to a matched group treated via conventional stenting.

RESULTS

The primary endpoint was reached in 14/15 patients (93%). There were no significant differences in procedural (58.6 min ± 12.7 vs. 57.4 min ± 14.2) or fluoroscopy times (10.0 min ± 4.3 vs.10.1 min ± 3.9) or contrast agent use (193.7 ml ± 54.8 vs. 181.4 ml ± 35.6). However, there were significant reductions in materials used in the study group compared to the control group equating to cost savings of almost US $600 per case (US $212.44 ± 258.09 vs. US $804.69 ± 468.11; P = 0.001).

CONCLUSIONS

Direct stenting using a novel bare metal stent with an IDS via 5 F diagnostic catheters is a viable alternative to conventional stenting in selected patients and is associated with significant cost savings.

Amplatzer left atrial appendage occlusion: single center 10-year experience

OBJECTIVES

To report a 10-year single center experience with Amplatzer devices for left atrial appendage (LAA) occlusion.

BACKGROUND

Intermediate-term outcome data following LAA occlusion are scarce.

METHODS

Short- and intermediate-term outcomes of patients who underwent LAA occlusion were assessed. All procedures were performed under local aesthesia without transesophageal echocardiography. Patients were discharged on acetylsalicylic acid and clopidogrel for 1-6 months.

RESULTS

LAA occlusion was attempted in 152 patients (105 males, age 72 ± 10 years, CHA2 DS2 -Vasc-score 3.4 ± 1.7, HAS-BLED-score 2.4 ± 1.2). Nondedicated devices were used in 32 patients (21%, ND group) and dedicated Amplatzer Cardiac Plugs were used in 120 patients (79%, ACP group). A patent foramen ovale or atrial septal defect was used for left atrial access and closed at the end of LAA occlusion in 40 patients. The short-term safety endpoints (procedural complications, bleeds) occurred in 15 (9.8%) and the efficacy endpoints (death, stroke, systemic embolization) in 0 patients. Device embolization occurred more frequently in the ND as compared to the ACP group (5 patients or 12% vs. 2 patients or 2%). Mean intermediate-term follow up of the study population was 32 months (range 1-120). Late deaths occurred in 15 patients (5 cardiovascular, 7 noncardiac, 3 unexplained). Neurologic events occurred in 2, peripheral embolism in 1, and major bleeding in 4 patients. The composite efficacy and safety endpoint occurred in 7% and 12% of patients.

CONCLUSION

LAA closure may be a good alternative to oral anticoagulation. This hypothesis needs to be tested in a randomized clinical trial to ensure that all potential biases of this observational study are accounted for.

Percutaneous closure of patent foramen ovale in cryptogenic embolism

BACKGROUND

The options for secondary prevention of cryptogenic embolism in patients with patent foramen ovale are administration of antithrombotic medications or percutaneous closure of the patent foramen ovale. We investigated whether closure is superior to medical therapy.

METHODS

We performed a multicenter, superiority trial in 29 centers in Europe, Canada, Brazil, and Australia in which the assessors of end points were unaware of the study-group assignments. Patients with a patent foramen ovale and ischemic stroke, transient ischemic attack (TIA), or a peripheral thromboembolic event were randomly assigned to undergo closure of the patent foramen ovale with the Amplatzer PFO Occluder or to receive medical therapy. The primary end point was a composite of death, nonfatal stroke, TIA, or peripheral embolism. Analysis was performed on data for the intention-to-treat population.

RESULTS

The mean duration of follow-up was 4.1 years in the closure group and 4.0 years in the medical-therapy group. The primary end point occurred in 7 of the 204 patients (3.4%) in the closure group and in 11 of the 210 patients (5.2%) in the medical-therapy group (hazard ratio for closure vs. medical therapy, 0.63; 95% confidence interval [CI], 0.24 to 1.62; P=0.34). Nonfatal stroke occurred in 1 patient (0.5%) in the closure group and 5 patients (2.4%) in the medical-therapy group (hazard ratio, 0.20; 95% CI, 0.02 to 1.72; P=0.14), and TIA occurred in 5 patients (2.5%) and 7 patients (3.3%), respectively (hazard ratio, 0.71; 95% CI, 0.23 to 2.24; P=0.56).

CONCLUSIONS

Closure of a patent foramen ovale for secondary prevention of cryptogenic embolism did not result in a significant reduction in the risk of recurrent embolic events or death as compared with medical therapy. (Funded by St. Jude Medical; ClinicalTrials.gov number, NCT00166257.).

Death by patent foramen ovale in a soccer player

A 34-year-old male patient was referred for primary percutaneous coronary intervention for ST-segment elevation myocardial infarction with cardiogenic shock and was found to have embolic left coronary artery occlusion and subsegmental pulmonary artery emboli as a consequence of venous thrombosis to trauma to the thigh in the presence of a patent foramen ovale.

Atrial fibrillation and aortic stenosis: impact on clinical outcomes among patients undergoing transcatheter aortic valve implantation

BACKGROUND

Atrial fibrillation (AF) is an important risk factor for stroke and is common among elderly patients undergoing transcatheter aortic valve implantation. The aim of this study was to assess the impact of AF on clinical outcomes among patients undergoing transcatheter aortic valve implantation.

METHODS AND RESULTS

Between August 2007 and October 2011, a total of 389 high-risk patients undergoing transcatheter aortic valve implantation were included into a prospective registry. AF was recorded in 131 patients (33.7%) with a mean CHA(2)DS(2)-VASC score of 4.5±1.2 and was paroxysmal in 26 (25.0%), persistent in 8 (7.7%), and permanent in 70 patients (67.3%). Patients with and without AF had similar baseline characteristics except for fewer revascularization procedures (coronary artery bypass grafting: 12% versus 22%; P=0.03) among AF patients. At 1 year, all-cause mortality was higher among patients with AF (30.9%) compared with those without AF (13.9%; hazard ratio [HR], 2.36; 95% confidence interval [CI], 1.43-3.90; P=0.0008). This was observed irrespective of the type of AF (permanent, HR, 2.47; 95% CI, 1.40-4.38; persistent, HR, 3.60; 95% CI, 1.10-11.78; paroxysmal, HR, 2.88; 95% CI, 1.37-6.05). Mortality gradually increased with higher CHA(2)DS(2)-VASC scores (score 1-3: HR, 2.20; 95% CI, 0.92-5.27; score 6-8: HR, 4.12; 95% CI, 2.07-8.20). The risks of stroke (3.9% versus 5.1%; HR, 0.76; 95% CI, 0.23-1.96; P=0.47) and life-threatening bleeding (19.8% versus 14.7%; HR, 1.37; 95% CI, 0.86-2.19; P=0.19) were similar among patients with and without AF.

CONCLUSIONS

AF is common among high-risk patients with severe aortic stenosis undergoing transcatheter aortic valve implantation and is associated with a >2-fold increased risk of all-cause and cardiovascular mortality, irrespective of the type of AF. The gradient of risk directly correlates with the CHA(2)DS(2)-VASC score.

Predictors of Clinical Outcomes in Patients With Severe Aortic Stenosis Undergoing TAVI

Background—

Patients with severe aortic stenosis at increased surgical risk continue to experience compromised long-term survival despite successful transcatheter aortic valve implantation. We used time-related pathways in a multistate analysis to identify predictors of adverse long-term outcome in patients who underwent transcatheter aortic valve implantation.

Methods and Results—

In a cohort of 389 patients with a mean age of 82.4±5.8 years and a STS score of 6.8±5.3 undergoing transcatheter aortic valve implantation between 2007 and 2011, multistate analysis was used to estimate mortality and stroke taking into account intercurrent events including kidney injury and the composite of access site and bleeding complications (ABC). Transapical access emerged as a predictor of kidney injury (hazard ratio [HR], 2.12; 95% confidence interval [CI] 1.00–4.47) and ABC (HR, 1.78; 95% CI, 1.07–2.96), but had no impact on the risk of stroke or death. Body mass index ≤20 kg/m 2 increased the risk of stroke or death (HR, 2.64; 95% CI, 1.25–5.54). Age >80 years (HR, 3.15; 95% CI, 1.11–8.92), body mass index ≤20 kg/m 2 (HR, 4.11; 95% CI, 1.33–12.70), prior stroke (HR, 16.42; 95% CI, 3.63–74.21), and presence of atrial fibrillation at baseline (HR, 4.12; 95% CI, 1.87–9.97) increased the risk of stroke and death after an intercurrent event of ABC.

Conclusions—

A body mass index ≤20 kg/m 2 was identified as a primary predictor of stroke and death after transcatheter aortic valve implantation during long-term follow-up, whereas transapical access emerged as a predictor of kidney injury and ABC. Age >80 years, body mass index ≤20 kg/m 2 , prior stroke, and presence of atrial fibrillation at baseline increased the risk of stroke and death after an intercurrent event of ABC.

Percutaneous management of vascular complications in patients undergoing transcatheter aortic valve implantation

OBJECTIVES

This study sought to investigate the feasibility and safety of percutaneous management of vascular complications after transcatheter aortic valve implantation (TAVI).

BACKGROUND

Vascular complications after TAVI are frequent and outcomes after percutaneous management of these adverse events not well established.

METHODS

Between August 2007 and July 2010, 149 patients underwent transfemoral TAVI using a percutaneous approach. We compared outcomes of patients undergoing percutaneous management of vascular complications with patients free from vascular complications and performed duplex ultrasonography, fluoroscopy, and multislice computed tomography during follow-up.

RESULTS

A total of 27 patients (18%) experienced vascular complications consisting of incomplete arteriotomy closure (n = 19, 70%), dissection (n = 3, 11%), arterial perforation (n = 3, 11%), arterial occlusion (n = 1, 4%), and pseudoaneurysm (n = 1, 4%). Percutaneous stent graft implantation was successful in 21 of 23 (91%) patients, whereas 2 patients were treated by manual compression, 2 patients underwent urgent surgery, and 2 patients required delayed surgery. Rates of major adverse cardiac events at 30 days were similar among patients undergoing percutaneous management of vascular complications and those without vascular complications (9% vs. 8%, p = 1.00). After a median follow-up of 10.9 months, imaging showed no evidence of hemodynamically significant stenosis (mean peak velocity ratio: 1.2 ± 0.4). Stent fractures were observed in 4 stents (22%, type I [6%], type II [16%]) and were clinically silent in all cases.

CONCLUSIONS

Vascular complications after TAVI can be treated percutaneously as a bailout procedure with a high rate of technical success, and clinical outcomes are comparable to patients without vascular complications. Stent patency is high during follow-up, although stent fractures require careful scrutiny.

Second valve implantation for the treatment of a malpositioned transcatheter aortic valve

BACKGROUND

Unfavorable immediate or delayed results after transcatheter aortic valve implantation (TAVI) may be a consequence of bioprosthesis malfunctioning, malpositioning, embolization, or degeneration. Deployment of a second valve within the first one implanted (TAVI-in-TAV) may be a potentially helpful therapeutic strategy.

METHODS

Six out of 412 patients undergoing TAVI had TAVI-in-TAV implantation for the treatment of a too high (n = 4) or too low position (n = 2) of the first implanted valve.

RESULTS

All TAVI-in-TAV procedures were successfully performed. The calculated valve area after second valve implantation was 1.6 ± 0.3 cm(2) with a mean gradient of 7.3 ± 2.2 mm Hg. Residual aortic regurgitation (AR) was mild in 5 patients and moderate in 1. At mid-term follow-up (30-724 days) neither the mean valve area (1.47 ± 0.31 cm(2)), the mean gradient (7.5 ± 3.6 mm Hg; 3.0-13.0 mm Hg) nor the degree of AR had changed significantly.

CONCLUSION

TAVI-in-TAV for correction of malpositioned or embolized valves is technically feasible and leads to favorable functional results during mid-term follow-up.

Iyengar yoga increases cardiac parasympathetic nervous modulation among healthy yoga practitioners

Relaxation techniques are established in managing of cardiac patients during rehabilitation aiming to reduce future adverse cardiac events. It has been hypothesized that relaxation-training programs may significantly improve cardiac autonomic nervous tone. However, this has not been proven for all available relaxation techniques. We tested this assumption by investigating cardiac vagal modulation during yoga.We examined 11 healthy yoga practitioners (7 women and 4 men, mean age: 43 ± 11; range: 26–58 years). Each individual was subjected to training units of 90 min once a week over five successive weeks. During two sessions, they practiced a yoga program developed for cardiac patients by B.K.S. Iyengar. On three sessions, they practiced a placebo program of relaxation. On each training day they underwent ambulatory 24 h Holter monitoring. The group of yoga practitioners was compared to a matched group of healthy individuals not practicing any relaxation techniques. Parameters of heart rate variability (HRV) were determined hourly by a blinded observer. Mean RR interval (interval between two R-waves of the ECG) was significantly higher during the time of yoga intervention compared to placebo and to control (P < 0.001 for both). The increase in HRV parameters was significantly higher during yoga exercise than during placebo and control especially for the parameters associated with vagal tone, i.e. mean standard deviation of NN (Normal Beat to Normal Beat of the ECG) intervals for all 5-min intervals (SDNNi, P < 0.001 for both) and root mean square successive difference (rMSSD, P < 0.01 for both). In conclusion, relaxation by yoga training is associated with a significant increase of cardiac vagal modulation. Since this method is easy to apply with no side effects, it could be a suitable intervention in cardiac rehabilitation programs.

Effect of biolimus-eluting stents with biodegradable polymer vs bare-metal stents on cardiovascular events among patients with acute myocardial infarction: the COMFORTABLE AMI randomized trial

CONTEXT

The efficacy and safety of drug-eluting stents compared with bare-metal stents remains controversial in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI).

OBJECTIVE

To compare stents eluting biolimus from a biodegradable polymer with bare-metal stents in primary PCI.

DESIGN, SETTING, AND PATIENTS

A prospective, randomized, single-blinded, controlled trial of 1161 patients presenting with STEMI at 11 sites in Europe and Israel between September 19, 2009, and January 25, 2011. Clinical follow-up was performed at 1 and 12 months.

INTERVENTION

Patients were randomized 1:1 to receive the biolimus-eluting stent (n = 575) or the bare-metal stent (n = 582).

MAIN OUTCOME MEASURES

Primary end point was the rate of major adverse cardiac events, a composite of cardiac death, target vessel-related reinfarction, and ischemia-driven target-lesion revascularization at 1 year.

RESULTS

Major adverse cardiac events at 1 year occurred in 24 patients (4.3%) receiving biolimus-eluting stents with biodegradable polymer and 49 patients (8.7%) receiving bare-metal stents (hazard ratio [HR], 0.49; 95% CI, 0.30-0.80; P = .004). The difference was driven by a lower risk of target vessel-related reinfarction (3 [0.5%] vs 15 [2.7%]; HR, 0.20; 95% CI, 0.06-0.69; P = .01) and ischemia-driven target-lesion revascularization (9 [1.6%] vs 32 [5.7%]; HR, 0.28; 95% CI, 0.13-0.59; P < .001) in patients receiving biolimus-eluting stents compared with those receiving bare-metal stents. Rates of cardiac death were not significantly different (16 [2.9%] vs 20 [3.5%], P = .53). Definite stent thrombosis occurred in 5 patients (0.9%) treated with biolimus-eluting stents and 12 patients (2.1%; HR, 0.42; 95% CI, 0.15-1.19; P = .10) treated with bare-metal stents.

CONCLUSION

Compared with a bare-metal stent, the use of biolimus-eluting stents with a biodegradable polymer resulted in a lower rate of the composite of major adverse cardiac events at 1 year among patients with STEMI undergoing primary PCI.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00962416.

Long-term comparison of everolimus- and sirolimus-eluting stents in patients with acute coronary syndromes

OBJECTIVES

The goal of this study was to compare the long-term clinical outcome between everolimus-eluting stent (EES) and sirolimus-eluting stent (SES) in patients with acute coronary syndromes (ACS).

BACKGROUND

EES have not been directly compared with SES in ACS patients to date.

METHODS

Between 2004 and 2009, 1,746 consecutive ACS patients (ST-segment elevation ACS [STE-ACS]: 33.5%; non-ST-segment elevation ACS [NSTE-ACS]: 66.5%) were treated with EES (n=903) or SES (n=843). Using propensity score matching, clinical outcome was compared among 705 matched pairs of ACS patients treated with EES and SES.

RESULTS

Through 3 years, the primary endpoint-the composite of death, myocardial infarction (MI), and target vessel revascularization (TVR)-occurred in 13.8% of EES- and 17.7% of SES-treated ACS patients (hazard ratio [HR]: 0.72, 95% confidence interval [CI]: 0.54 to 0.95, p=0.02). The difference in favor of EES was driven by a lower risk of TVR (5.7% vs. 8.8%, HR: 0.65, 95% CI: 0.43 to 0.98, p=0.04) and a trend toward a lower risk of MI (2.1% vs. 3.3%, HR: 0.56, 95% CI: 0.29 to 1.12, p=0.10). The risk of death (7.2% vs. 8.8%, HR: 0.75, 95% CI: 0.50 to 1.10, p=0.14) showed no difference between EES and SES. The treatment effect in favor of EES for the primary endpoint was similar for patients with STE-ACS (16.4% vs. 18.5%, HR: 0.80, 95% CI: 0.50 to 1.27) and NSTE-ACS (12.4% vs. 17.3%; HR: 0.67, 95% CI: 0.47 to 0.96; pfor interaction=0.56) and across major subgroups. Definite (0.4% vs. 1.8%, p=0.03), and definite or probable stent thrombosis (3.4% vs. 6.1%, p=0.02) were less frequent among EES- than SES-treated ACS patients.

CONCLUSIONS

Among patients with ACS, the unrestricted use of EES is associated with improved clinical outcome compared with SES during long-term follow-up to 3 years. Notably, the risk of stent thrombosis was lower among EES-treated ACS patients.

Left atrial appendage closure with the Amplatzer cardiac plug in patients with atrial fibrillation

BACKGROUND

Percutaneous left atrial appendage closure (LAAC) has emerged as an alternative to oral anticoagulation (OA) for prevention of thromboembolic stroke in patients with non-valvular atrial fibrillation (NVAF).

OBJECTIVE

To describe the immediate results and short- to medium-term clinical follow-up (FU) of patients that underwent LAAC with Amplatzer Cardiac Plug (ACP) implantation in a single reference center.

METHODS

Eighty-six consecutive patients with NVAF, contraindication to OA, and CHADS2 score=2.6 ± 1.2 underwent LAAC with ACP implantation. Clinical and echocardiographic FU was performed at least four months after the procedure.

RESULTS

All implants were guided by angiography alone. Procedural success was 99% (one patient suffered a cardiac tamponade requiring pericardiocentesis, and the procedure was waived). There were four major complications (the already mentioned cardiac tamponade, two transient ischemic attacks and one device embolization with percutaneous retrieval) and two minor complications (one pericardial effusion without clinical significance and one non-significant ASD evidenced at FU). There was one in-hospital death after six days, unrelated to the procedure. All other patients were discharged without OA. After 25.9 patient-years of FU (69 patients), there were no strokes and no late device embolization. The LAA was completely closed in 97% of the cases. Six patients showed evidence of thrombus formation on the device, which resolved after three months of OA.

CONCLUSION

LAAC is associated with high success, acceptable complication rates, and promising FU results, and may be considered a valuable alternative or complement to OA for stroke prevention in patients with NVAF.