Jan Jastrzębski

Computed tomography angiography for prediction of atrial fibrillation after coronary artery bypass grafting: Proof of concept

BACKGROUND Postoperative atrial fibrillation (AF) is a serious complication of coronary artery bypass grafting (CABG). There are scant data on the application of coronary computed tomography angiography (CCTA) for prediction of postoperative AF. METHODS A total of 102 patients (77 male, mean age: 64±10 years) with pre-procedural CCTA undergoing isolated CABG were enrolled. Clinical risk factors were collected. Qualitative and quantitative CCTA analysis of the atria, pulmonary veins (PV), and epicardial adipose tissue (EAT) along the left atrium (LA) was performed to determine the predictors for postoperative AF. The primary endpoint was defined as any in-hospital AF requiring treatment. RESULTS Postoperative AF occurred in 24% of patients. Patients with AF had higher body mass index (29.7±4.8kg/m(2) vs 27.3±3.9kg/m(2), p=0.013), larger right atrial area (25.4±5.3cm(2) vs 22.3±6.4cm(2), p=0.035), LA systolic volume (114.7±32.8ml vs 96.8±30.4ml, p=0.015), LA EAT volume (5.6±3ml vs 4±2.5ml, p=0.009), and right superior PV ostium area (3.8±1.3cm(2) vs 3±1cm(2), p=0.021) compared to non-AF patients. By multivariable analysis, only LA EAT volume [odds ratio (OR): 1.21, 95% confidence interval (CI): 1.01-1.44, p=0.036] and right superior PV ostium area (OR: 1.63, 95% CI: 1.06-2.50, p=0.026) were independent predictors of AF. The optimal cut-offs for LA EAT volume and right superior PV ostium were >3.4ml and >4.1cm(2), respectively (max. sensitivity: 83%, max. specificity: 86%). CONCLUSIONS Increased LA EAT and right superior PV ostial size are independently associated with AF after CABG. CCTA might be used as a noninvasive prediction tool for AF in patients undergoing CABG.

Transcatheter aortic valve implantation in patients with bicuspid aortic valve: a series of cases

BACKGROUND Bicuspid aortic valve (BAV) has been considered a relative contraindication for transcatheter aortic valve implantation (TAVI). Due to more oval shape of the BAV annulus compared to tricuspid aortic valve, the procedure has been discouraged because of an increased risk of stent assembly displacement, uneven expansion, post-procedure paravalvular leakage, stent valve distortion, or other malfunction after implantation. For the same reasons patients with BAV have been excluded from the majority of clinical TAVI trials. AIM To evaluate the efficacy and safety of TAVI in patients with BAV stenosis. METHODS We analysed a group of 104 patients admitted to our institution for TAVI between January 2009 and May 2012. During pre-procedure evaluation, transthoracic and transoesophageal (TEE) echocardiography as well as angio-computed tomography (CT) scan were performed to assess aortic valve anatomy and morphology. Appropriate measurements and detailed analyses of imaging data have been accomplished to select optimal access site, prosthesis size as well as to plan the procedure. BAVs were recorded in seven patients (6.7%; mean age 77.7 years). These patients presented with severe symptomatic aortic valve stenosis with a mean aortic valve area of 0.55 cm² (0.46-0.7 cm²) as measured in TEE. All of the patients had been disqualified from surgical valve replacement due to high surgical risk with a mean logistic Euroscore of 19.9%. All of them successfully underwent TAVI using CoreValve (n = 5) or Sapien (n = 2) valves. Follow-up was completed at 30 days, and six and 12 months after the procedure. RESULTS During follow-up one patient developed an elliptic distortion of the aortic prosthesis in CT, although it did not result in significant malfunctioning of the implant. One patient died of infective endocarditis 30 days after the procedure. Survivors at 30-day follow-up had mild to moderate aortic insufficiency, and it did not deteriorate after six months. At one year follow-up six out of seven patients remained alive. They achieved significant functional improvement by New York Heart Association class compared to baseline. CONCLUSIONS TAVI may constitute an alternative treatment option for high-risk patients with BAV, resulting in a low periprocedural mortality rate, and good 30-day, six-month, and one-year outcomes.

Second transcatheter aortic valve implantation for treatment of suboptimal function of previously implanted prosthesis: review of the literature.

OBJECTIVES To systematically review reported cases of second transcatheter aortic valve deployment within a previously implanted prosthesis (TAV-in-TAV). BACKGROUND TAV-in-TAV deployment is one of the rescue strategies undertaken due to an unsuccessful or suboptimal transcatheter aortic valve implantation (TAVI) result. Currently, there are no clear indications for second valve implantation and outcomes of patients with 2 prostheses deployed remain poorly known. METHODS The MEDLINE and PubMed databases were searched for cases of TAV-in-TAV implantations of aortic valve. RESULTS Forty-three articles reporting on TAV-in-TAV deployment were included in the review. The most frequently observed indication for second valve implantation was aortic regurgitation (AR) occurring shortly after TAVI. There was a strong dominance of paravalvular over intravalvular AR, with prosthesis malposition being the main underlying cause of TAVI failure (81% of all identified cases). Perioperative echocardiographic images are crucial in identifying causes of failure and helpful in optimal rescue strategy selection. Success rate of TAV-in-TAV implantation varies from 90% to 100% with mortality rate of 0-14.3% at 30 days. Despite similar aortic valve function in follow-up, TAV-in-TAV may be an independent predictor of increased cardiovascular mortality. CONCLUSIONS TAV-in-TAV implantation is feasible and results in favorable short- and mid-term outcomes in patients with acute failure of TAVI without recourse to open-heart surgery. Further studies are needed to establish algorithm of the management of unsuccessful or suboptimal implantation results.

Mitral and aortic regurgitation following transcatheter aortic valve replacement

Objective To analyse the impact of postprocedural mitral regurgitation (MR), in an interaction with aortic regurgitation (AR), on mortality following transcatheter aortic valve implantation (TAVI). Methods To assess the interaction between MR and AR, we compared the survival rate of patients (i) without both significant MR and AR versus (ii) those with either significant MR or significant AR versus (iii) with significant MR and AR, all postprocedure. 381 participants of the Polish Transcatheter Aortic Valve Implantation Registry (166 males (43.6%) and 215 females (56.4%), age 78.8±7.4 years) were analysed. Follow-up was 94.1±96.5 days. Results Inhospital and midterm mortality were 6.6% and 10.2%, respectively. Significant MR and AR were present in 16% and 8.1% patients, including 3.1% patients with both significant MR and AR. Patients with significant versus insignificant AR differed with respect to mortality (log rank p=0.009). This difference was not apparent in a subgroup of patients without significant MR (log rank p=0.80). In a subgroup of patients without significant AR, there were no significant differences in mortality between individuals with versus without significant MR (log rank p=0.44). Significant MR and AR had a significant impact on mortality only when associated with each other (log rank p<0.0001). At multivariate Cox regression modelling concomitant significant MR and AR were independently associated with mortality (OR 3.2, 95% CI 1.54 to 5.71, p=0.002). Conclusions Significant MR or AR postprocedure, when isolated, had no impact on survival. Combined MR and AR had a significant impact on a patients prognosis.

Comparison of Stent Length Reported by the Stent's Manufacturer to That Determined by Quantitative Coronary Angiography at the Time of Implantation Versus That Determined by Coronary Computed Tomographic Angiography at a Later Time

The aim of this study was to assess whether coronary computed tomographic angiography (CCTA) would allow accurate length measurements that may help select optimal stent length. In 19 patients who underwent stent implantation and CCTA, the lengths of 30 implanted stents were assessed independently using quantitative coronary angiography (QCA) at the time of implantation and CCTA during follow-up. Measurements on CCTA and QCA were compared with the actual lengths of the implanted stents. The mean actual stent length was 17.3 ± 6.3 mm; the mean length of the stents measured using CCTA was 17.25 ± 5.54 mm, and the mean length of the stents measured using QCA was 15.92 ± 5.86 mm. There was a stronger positive correlation between measurements on CCTA versus actual stent lengths (R = 0.99, p = 0.0001) than between measurements on QCA versus actual stent lengths (R = 0.82, p = 0.0001) (p <0.0001 for the difference between correlation coefficients). In conclusion, the length measurements obtained with CCTA correlate better with an anatomic gold standard (actual stent lengths) than those obtained using QCA.

Relation between coronary plaque calcium deposits as described by computed tomography coronary angiography and acute results of stent deployment as assessed by intravascular ultrasound

Introduction The findings from intravascular ultrasound studies on the impact of calcium deposits on the results of stent implantation are conflicting. Aim To evaluate whether calcium deposits as assessed by (CTCA) influence results of stent deployment. Material and methods The study population comprised 60 patients (43 male; age 64.2 ±8.6 years) who underwent CTCA before stent implantation. Lesion calcium score, total calcium length, and maximal area and maximal thickness of calcium deposits within the lesion segment were assessed. Plaques were divided into those with calcium score ≥ median (group 1), calcium score < median (group 2), and without calcium (group 3). Intravascular ultrasound (IVUS) was performed after attainment of optimal angiographic results of the stent procedure. Focal and diffuse stent expansion was defined as either minimum stent area (MSA) or mean stent area over the length of the stent divided by reference lumen area. Results The proximal reference segments of lesions with higher calcium score contained a larger plaque burden (47 ±12% vs. 41 ±9% vs. 34 ±18%, p = 0.02) – respectively for groups 1, 2, and 3. Positive correlation was observed between lesion calcium score and frequency of post-dilation (R = 0.28, p = 0.03). There was no difference in focal stent expansion (71 ±14% vs. 65 ±15% vs.71 ±15%, p = 0.3) or diffuse stent expansion (92 ±30% vs. 85 ±30% vs. 93 ±38%, p = 0.7) comparing groups 1, 2, and 3. Lesion calcium score, total length of calcium, and maximum area and thickness of calcium deposits did not correlate with focal or diffuse stent expansion. Conclusions Lesions with a higher CTCA calcium score had larger reference plaque burden after stent implantation and more likely required post-dilation, but final stent expansion as assessed by IVUS was not affected by the amount of CTCA calcium provided an angiographically optimal result was achieved.

Comparison of mid-term results of transcatheter aortic valve implantation in high-risk patients with logistic EuroSCORE ≥ 20% or < 20.

BACKGROUND Transcatheter aortic valve implantation (TAVI) is an established treatment method in selected high-risk patients with severe aortic stenosis. However, data on which patients gain most benefit from this procedure is still limited. According to the European consensus document, TAVI is recommended for high-risk patients with logistic EuroSCORE (log ES) ≥ 20%. To date, little is known about TAVI outcomes in patients with log ES < 20%. AIM To evaluate outcomes of TAVI in high-risk patients with log ES ≥ 20% in comparison with high-risk patients with log ES < 20%. METHODS AND RESULTS Of 93 patients who underwent TAVI at our institution between January 2009 and December 2011, we identified 59 (63.4%) patients with log ES ≥ 20% (Group 1) and 34 (36.6%) patients with log ES < 20% (Group 2). The mean log ES was 30.9 ± 9.7% in Group 1 and 12.7 ± 4.9% in Group 2 (p < 0.01). Significant differences were found between the two groups in regard to age (82.9 ± 5.9 vs. 78.7 ± 7.8 years, p = 0.001), left ventricular ejection fraction (51.5 ± 14% vs. 60.4 ± 9.6%, p = 0.002), pulmonary artery systolic pressure (56 ± 11 vs. 49 ± 10.6 mm Hg, p = 0.02), and glomerular filtration rate (51.3 ± 18.4 vs. 60.6 ± 16.6 mL/min/m2, p = 0.02). Survival rates at 1 and 2 years were 76.6% and 69.0% in Group 1 and 89.0% and 83.6% in Group 2 (p = NS). However, cardiovascular mortality at 1 and 2 years was higher in Group 1 compared to Group 2 (21.4% and 28.6% vs. 8.1% and 10.8% in Groups 1 and 2, respectively). CONCLUSIONS The results of this study demonstrate that at 2 years of follow-up, TAVI in high-risk patients with log ES ≥ 20% was associated with a higher cardiovascular mortality compared to high-risk patients with log ES < 20%.

Comparison of Plaque Burden and Vessel Remodeling in Obstructive Saphenous Vein Graft Lesions as Assessed by Intravascular Ultrasound and Dual-source Computed Tomography.

Purpose: The aim of our study was to compare plaque burden and vessel remodeling of obstructive saphenous vein graft (SVG) lesions as assessed by dual-source computed tomography (DSCT) and intravascular ultrasound (IVUS). Materials and Methods: Preintervention DSCT examination and IVUS were performed in consecutive patients before percutaneous treatment of the SVG lesion. SVG vessel and lumen areas were measured with use of DSCT and IVUS at the minimal lumen area (MLA) site and at proximal and distal reference sites. Plaque burden was defined as the ratio of plaque and vessel area. Remodeling index was defined as the ratio of the SVG area at the MLA site to the mean reference SVG area. Results: Twenty-four obstructive SVG lesions were imaged with DSCT and IVUS before stent implantation in 24 patients. The SVG cross-sectional area at the MLA site measured by IVUS and DSCT was similar (17.0±4.5 vs. 17.3±5.3 mm2, P=0.6) and well correlated (R=0.77, P<0.001). Similarly, plaque burden and remodeling index assessments did not differ significantly between the 2 imaging modalities (79.0%±4.0% vs. 81.0%±8.0%, P=0.18, and 1.09±0.22 vs. 1.07±0.32, P=0.7 for IVUS vs. DSCT for plaque burden and remodeling, respectively). The correlation between IVUS-assessed and DSCT-assessed plaque burden and remodeling index was moderate to good (R=0.55, P=0.01 and R=0.77, P<0.001, respectively, for plaque burden and remodeling index). Conclusions: There is moderate to good correlation between DSCT and IVUS in the assessment of vessel remodeling and plaque burden in obstructive SVG lesions. Noninvasive assessment and monitoring of SVG disease is feasible using DSCT.

Lidocaine bolus may facilitate computed tomographic coronary angiography in patients with frequent premature ventricular contractions

Introduction Heart rate irregularities are the major limitations of computed tomographic coronary angiography (CTCA) due to severe motion artifacts. Aim To evaluate the safety and efficacy of a lidocaine intravenous bolus in preserving good image quality by the transient suppression of premature ventricular contractions (PVC) during the CTCA scan. Material and methods The study group comprised 67 consecutive patients with sinus rhythm and numerous PVC scheduled for CTCA. Intravenous boluses of 25–50 mg lidocaine were given after calcium score assessment and immediately before CTCA. The control group comprised 67 patients with sinus rhythm without PVC matched according to the body mass index (BMI), age, sex, and calcium score. All coronary vessel segments were assessed for image quality and presence of significant stenosis. Results As compared with calcium score assessment, after administration of lidocaine and during the CTCA scan PVC were completely suppressed in 22 (40%), reduced in 10 (18%), unchanged in 18 (32%), and intensified in 5 (10%) patients. Overall, there were 32 (58%) patients with sinus rhythm during CTCA as compared with only 11 (20%) patients free from PVC during calcium score assessment (p < 0.001). Image quality in 871 coronary segments including both the study group and control patients was worse in patients with PVC (p < 0.0001). However, there was no statistically significant difference in the number of patients with at least one segment of non-diagnostic quality (6% vs. 12%, p = 0.36; respectively). Conclusions Single lidocaine bolus given prior to CTCA is safe, may temporarily eliminate or reduce the intensity of arrhythmia, and hence results in improved quality of CTCA in patients with numerous PVC.