On-treatment platelet reactivity before coronary artery bypass surgery is associated with in-hospital major bleeding

Abstracts / Cardiovascular Revascularization Medicine 13 (2012) 147–156

introduced in the renal artery, and the following measurements were obtained or calculated: average peak velocity (APV), renal flow reserve (RFR), and resistive index (RI). Measurements were obtained at baseline and under hyperemic condition induced by a bolus of dopamine (50 μg/kg) given intrarenally. RFR was calculated as the ratio of hyperemic to basal peak velocity. RI was estimated as (peak systolic velocity−end-diastolic velocity)/peak systolic velocity. APV, RFR, and RI were measured before and after RSD and 1 month later. The RSD was achieved via the lumen of the main renal artery with the catheter connected to a radiofrequency generator from St. Jude Medical according to prespecified algorithm. Samples for plasma norepinephrine were collected at baseline and at 1 month after ablation. Results: In the acute phase, APV increased by 300% postablation 300% higher (65.16±39.78 vs. 21.79±8.53 cm/s, Pb.0001). Similarly, RFR decreased by 50% and RI decreased by 30% (RFR 1.51±0.59 vs. 2.96±1.33, Pb.0001 and RI 0.66±0.07 vs. 0.74±0.07, P=.003). At 1 month after RSD compared to APV remained significantly higher (30.21±13.14 vs. 21.79±8.53 cm/s, P=.035) compared to baseline. Radiofrequency RSD resulted in reduced RFR (1.36±0.25 vs. 2.96±1.33, Pb.0001), RI (0.48±0.15 vs. 0.74±0.07, P=.003), and plasma norepinephrine levels (11.08±6.19 vs. 17.76±11.9 pg/ml, P=.045). Conclusions: Catheter-based RSD results in acute increase in RBF and decrease in RFR, RI, and plasma catecholamines. These results are maintained at 1 month postablation. The acute findings can potentially be used as a measure of successful renal denervation. doi:10.1016/j.carrev.2012.01.061

Balloon aortic valvuloplasty for severe aortic stenosis as a bridge to transcatheter/surgical aortic valve replacement Itsik Ben-Dor, Israel M. Barbash, Danny Dvir, Gabriel Maluenda, Petros Okubagzi, Rebecca Torguson, Zhenyi Xue, Joseph Lindsay, Lowell F. Satler, Augusto D. Pichard, Ron Waksman Washington Hospital Center, Washington, DC Background: The introduction of transcatheter aortic valve implantation (TAVI) has led to a revival of balloon aortic valvuloplasty (BAV) as treatment of patients with severe aortic stenosis. Objectives: This study aimed to determine the outcome of BAV as a stand-alone therapy versus BAV as a bridge to TAVI/surgical aortic valve replacement (SAVR). Methods: A cohort of 472 patients underwent 538 BAV procedures. This cohort was divided into group I: BAV alone 387 (81.9%) and group II: BAV as bridge (85; 18.1%) to (65) TAVI or (20) SAVR. Clinical, hemodynamic, and follow-up mortality data were collected. Results: There was no significant difference between the two groups in the baseline characteristics (Table 1). The mean increase in aortic valve area was 0.39±0.25 in group I and 0.42±0.26 in group II, P=.33. The decrease in mean gradient was 24.1±13.1 in group I and 27.1±13.8 in group II, P=.06. During a median

Table 1 Variable

BAV-alone (N=387)

BAV-bridge (N=85)

P value

Mean age (year) Male (%) STS score (%) Renal insufficiency (CrCl b60 ml/min) (%) Atrial fibrillation (%) Ejection fraction (%) Aortic valve area before (cm2) Aortic valve area after (cm2)

81.9±8.3 165(42.6) 13.1±6.2 171(44.1)

81.9±10 39(45.8) 12.4±6.4 35(41.2)

.99 .47 .26 .81

141(36.4) 45.0±18.0 0.61±0.2 0.99±0.34

27(31.7) 45.8±17.1 0.57±0.18 1.0±0.35

.37 .7 .11 .84

151

Fig. 1.

follow-up of 183 days, the mortality rate was 55.2% (214 patients) in group I and 19 (22.3%) in group II during median follow-up of 378 days, Pb.001. (Fig. 1). Conclusion: In high-risk patients with aortic stenosis and temporary contraindications to SAVR or TAVI, BAV may be used as a bridge to intervention with good midterm outcomes. In others, BAV can be safely used but is associated with a poor outcome.

doi:10.1016/j.carrev.2012.01.062

On-treatment platelet reactivity before coronary artery bypass surgery is associated with in-hospital major bleeding Gabriel L. Sardi, Gabriel Maluenda, Michael A. Gaglia, Jr., Ana Laynez-Carnicero, Rebecca Torguson, Rajbabu Pakala, Israel M. Barbash, Zhenyi Xue, William O. Suddath, Kenneth M. Kent, Lowell F. Satler, Augusto D. Pichard, Ron Waksman Washington Hospital Center, Washington, DC Background: Patients often undergo coronary-artery bypass graft (CABG) within 5–7 days of thienopyridine therapy. Evidence supporting the use of on-treatment platelet reactivity testing before CABG is very limited. We hypothesized that low on-treatment platelet reactivity before CABG would be associated with higher in-hospital major bleeding (IHMB). Methods: On-treatment platelet reactivity was prospectively measured with Verify Now (VN) P2Y12 assay, vasodilator stimulated phosphoprotein phosphorylation (VASP), and light transmittance aggregometry (LTA) with 5 and 20 μM of ADP. The population consisted of 51 patients undergoing CABG within 5 days of thienopyridine discontinuation between August 2010 and May 2011. The primary end point was IHMB, defined as bleeding intracranially or that associated with hemodynamic compromise, a hemoglobin (Hb) drop of N5g/dl, or a hematocrit drop of N15%. The relation between platelet reactivity value and IHMB was assessed with Wilcoxon rank-sum test; its relation with Hb drop was evaluated with Spearman correlation. Results: The primary outcome (IHMB) occurred in 30 patients (58.8%).VASP and LTA 5 μM of ADP were associated with the primary end point (P=.001 and .03, respectively). Median VASP platelet reactivity index (PRI) was 56.7% in patients with IHMB and 73.7% in those without. The respective values of maximal platelet aggregation percentage by LTA 5 μM were 39% and 48%,

152

Abstracts / Cardiovascular Revascularization Medicine 13 (2012) 147–156

respectively. VN P2Y12 reaction units and VASP PRI were inversely correlated to the degree of hemoglobin drop after CABG (P=.0006 and .0012, respectively). Conclusion: Platelet reactivity testing with VASP and with LTA 5 μM of ADP before CABG appears to be associated with post-CABG IHMB. These tests could be used to risk stratify patients undergoing CABG within 5 days of thienopyridine discontinuation.

doi:10.1016/j.carrev.2012.01.063

Postoperative prosthesis insufficiency affects mortality in patients undergoing TAVI Francesca Giordana, Stefano Salizzoni, Walter Grosso Marra, Samuel Mancuso, Claudio Moretti, Michele La Torre, Maurizio D'amico, Mauro Giorgi, Imad Sheiban, Fiorenzo Gaita, Mauro Rinaldi San Giovanni Battista Molinette, Torino, Italy Background: TAVI is by now a valid therapeutic option in elderly patients (pts) with severe symptomatic aortic stenosis considered at high risk or with contraindication to aortic valve replacement (AVR). The impact of postprocedural leaks on mortality is still debated. Methods: Since May 2008 to July 2011, 100 consecutive pts underwent TAVI (60 Edwards Sapien Valve, 40 CoreValve). Transthoracic echocardiogram (TTE) was performed before discharge and after 3 months. Prosthesis insufficiency (PI) was considered significant if at least mild according to ASE and EAE recommendations. The aim of the study is to evaluate the effect of postprocedural periprosthetic and intraprosthetic leaks on mortality. Results: Retrograde approach was performed in 67 pts, while 33 pts benefited from the transapical access. Predischarge TTE was performed in all pts, and 24 had at least mild PI: 17 (70.8%) periprosthetic, 3 (12.5%) intraprosthetic, and 4 (16.7%) mixed. VARC mortality was 15%. At 3-month follow-up (range 36–126 days), all 85 alive pts underwent a TTE at our institution. Significant leaks were found in 24 (28.2%) pts: 18 (75%) periprosthetic, 1 (4.2%) intraprosthetic, and 5 (20.4%) mixed. The univariate analysis with Yatescorrected χ2 showed that postprocedural PI affects 1-year mortality (RR 2.68, IC 1.39–5.18, P=.009). Subgroups analysis showed an increased incidence of leaks in CoreValve group compared to the Edwards Sapien group (28/36 vs. 24/49, P=.02). Conclusion: Periprosthesis leaks, affected also by prosthesis choice, increase 1-year mortality in patients undergoing TAVI. These data confirm the actual limits of this procedure compared to AVR. In the near future, new technologies and devices could help to improve results.

doi:10.1016/j.carrev.2012.01.064

Denuded iliac endothelium with long-term high-cholesteroldiet-induced vascular dysfunction and accelerated atherosclerosis as well as neointimal formations after BMS implantation Jinsheng Li, Jianing Yue, Takamitsu Nakamura, Dongming Hou, Jeff White, Jaipal Singh, Nicolas Chronos Saint Joseph's Translational Research Institute, Atlanta, GA Background: High-cholesterol diet induces atherosclerotic lesions which can be accelerated by denudation of endothelium (EC). EC

denudation of iliac artery (IA) has not been well studied in the hyperlipemic rabbit. In this study, endothelial function and development atherosclerosis were investigated in nonstented (NSIA) and/or stented iliac artery (SIA). Methods: Nine rabbits were fed with atherogenic diet for 9 weeks. Cholesterol was measured before and after 1 week, 5 weeks, and 9 weeks of diet. At 1 week, 8 IAs were denuded EC (Group II) and 10 IAs kept the EC intact (Group I). At 5 weeks, eight BMSs (3.0/15 mm) were, respectively, implanted in Group Ib and Group IIb. At 9 weeks, the animals were sacrificed followed by angiograph, OCT, and IVUS (VH) images. NSIAs (Group Ia and IIa) were examined using organ chamber for vascular function. SIAs were embedded in plastic and stained with H&E and Movat. Aorta and NSIAs were embedded in paraffin and stained with H&E, Movat, SMA, and RAM-11. Results: Plasma cholesterol was increased after 1, 5, and 9 weeks of atherogenic diet. IA showed endothelium-dependent relaxation to acetylcholine (A.Ch) in Group Ia but was significantly inhibited in Group IIa (80.7%±7.4% vs. 31.2%±6.7% at 10 μM A.Ch; Pb.01). There was no difference in endothelium-independent relaxation to SNP (99.9%±0.1% vs. 90.0%±3.4% at 10 μM SNP; P=.06). Histological analysis revealed that aorta presented diffused plaques in both groups. Denudation of EC (IIa) accelerated plaques formation. There were abundant foam cells (RAM-11 positive) and spindle-shaped cells (SMA positive) in the lesions. The area of neointimal and atherosclerosis in IIb was significantly higher than that in Ib (6.13±0.40 vs. 3.60±0.45 mm2; Pb.001). All struts of stent were touched on the internal elastic lamina (IEL) in Ib, but only 65.6% struts touched in IIb. About one third of the struts were in contact with the plaques. These results were consistent with OCT and IVUS (VH). Conclusion: Long-term atherogenic diet induces diffuse plaques in the aorta but not in the iliac artery. EC denudation caused vascular dysfunction and accelerated plaque formation in the iliac artery. However, BMS did not inhibit plaque formation. Endothelial denudation provides a valuable model for DES study.

doi:10.1016/j.carrev.2012.01.065

Mitral regurgitation improves after TAVI Francesca Giordana, Michele Capriolo, Pierluigi Omedè, Stefano Salizzoni, Mauro Giorgi, Virginia Bovolo, Walter Grosso Marra, Simone Frea, Maurizio D'amico, Imad Sheiban, Mara Morello, Sebastiano Marra, Fiorenzo Gaita, Mauro Rinaldi San Giovanni Battista Molinette, Torino, Italy Background: Although it is known that mitral regurgitation improves after surgical aortic valve replacement (AVR) for aortic stenosis, nowadays, few and contradictory information are available about changes in mitral regurgitation (MR) severity after transcatheter aortic valve implantation (TAVI). Methods: Thirty-six patients (pts) with MR ≥2+/4+ without severe mitral stenosis who underwent TAVI (26 Edward Sapien Valve, 10 CoreValve) were consecutively enrolled. All pts underwent transthoracic echocardiography within 7 days before TAVI and 3 months after the procedure. MR was graded as none (0+/4+), trivial (1+/4+), mild (2+/4+), moderate (3+/4+), and severe (4+/4+) according with current EAE and ASE recommendations. Predefined parameters studied for MR evaluation were effective regurgitant orifice area (EROA) and MR index. Before TAVI, MR was classified as organic or functional according to valve morphology and left ventricular function. Results: At baseline, 4 pts had severe MR (4+/4+), 10 pts had moderate MR (3+/4+), and 22 had mild MR (2+/4+) with organic etiology in 30 (83.3%) pts and functional etiology in 6 (16.7%)