Cardiac resynchronization therapy using conduction system pacing after double-switch surgery for congenitally corrected transposition of the great arteries: a case report.

Background: Patients with congenitally corrected transposition of the great arteries (ccTGA) are at risk of developing conduction disease and complete atrio-ventricular block and this risk increases after corrective cardiac surgery. However, the optimum pacing modality remains controversial. Case summary: Twelve years after a double-switch surgery with ventricular septal defect correction, a 16-year-old ccTGA female was referred with an indication for cardiac resynchronization therapy. In the absence of coronary sinus (CS) or direct access to the conduction system, several therapeutic options were considered. Finally, using a three-dimensional navigation system and customized sheaths, a left bundle branch area pacing (LBBAP) lead was successfully implanted. The implantation resulted in stable pacing parameters and positive haemodynamic changes. At 9-month follow-up, pacing parameters were stable and the patient reported a significant improvement in quality of life. Discussion: Cardiac resynchronization therapy in adults with repaired congenital heart disease remains challenging, especially in the absence of CS or direct access to the conduction system. In such a situation, LBBAP appears as an attractive alternative pacing modality. However, pre-operative management is critical to the success of the implantation.

Inequality between women and men in ICD implantation.

Background: The impact of sex on ICD implantation practice and survival remain a topic of controversy. To assess sex-specific differences in ICD implantation practice we compared clinical characteristics and survival in women and men. Methods: From a nationwide registry, all new ICD implantations performed between 01/02/2010 and 31/01/2019 in Belgian patients were analyzed retrospectively. Baseline characteristics and survival rates were compared between sexes. To identify predictors of mortality, multivariable Cox regression was performed. Results: Only 3096 (20.9%) of 14,787 ICD implantations were performed in women. Within each type of underlying cardiomyopathy, the proportion women were lower than men. The main indication in men was ischemic vs dilated cardiomyopathy in women. Women were overall younger (59.1 ± 15.1 vs 62.6 ± 13.1 years; p < 0.001) and had less comorbidities except for oncological disease. More women functioned in NYHA-class III (33.6% vs 27.9%; p < 0.001) and had a QRS > 150 ms (29.4% vs 24.3%; p < 0.001), consistent with a higher use of CRT-D devices (31.7% vs 25.1%; p < 0.001). Women had more complications, reflected by the need to more re-interventions within 1 year (4.3% vs 2.7%, p < 0.001). After correction for covariates, sex-category was not a significant predictor of mortality (p = 0.055). Conclusion: There is a significant sex-disparity in ICD implantation rates, not fully explained by epidemiological differences in the prevalence of cardiomyopathies, which could imply an undertreatment of women. Women differ from men in baseline characteristics at implantation suggesting a selection bias. Further research is necessary to evaluate if women receive equal sudden cardiac death prevention.

Durable Physiological Changes and Decreased Syncope Burden 12 Months After Unifocal Right-Sided Ablation Under Computed Tomographic Guidance in Patients With Neurally Mediated Syncope or Functional Sinus Node Dysfunction.

[Figure: see text].

Prospective Randomized Evaluation of High Power During CLOSE-Guided Pulmonary Vein Isolation: The POWER-AF Study.

BACKGROUND: CLOSE-guided atrial fibrillation (AF) ablation is based on contiguous (intertag distance ≤6 mm), optimized (Ablation Index >550 anteriorly and >400 posteriorly) point-by-point radiofrequency lesions. The optimal radiofrequency power remains unknown. METHODS: The POWER-AF study is a prospective, randomized controlled monocentric study including patients with paroxysmal AF, planned for first CLOSE-guided pulmonary vein isolation using a contact force radiofrequency catheter (Thermocool SmartTouch, Biosense Webster, Inc, Irvine, CA). A total of 100 patients were randomized into 2 groups (1:1). The control group received AF ablation using the standard CLOSE protocol (35 W), whereas in the experimental group, pulmonary vein isolation was performed using high power (45 W). Endoscopic evaluation was performed in patients with intraesophageal temperature rise >38.5 °C. RESULTS: The resulting sample size was 96 (48+48) patients. In the high power group, shorter procedure time (80 versus 102 minutes, P<0.001), shorter total radiofrequency application time (16 versus 26 minutes, P<0.001), and radiofrequency time per application (26 versus 37 s anteriorly, P<0.001 and 13 versus 17 s posteriorly, P<0.001) were observed. Endoscopic evaluation (performed in 19/48 versus 25/48 patients respectively, P=0.31) showed an ulcerative perforation in a high power group patient (treated by endoscopic stenting and normalization after ≈4 months) and a superficial ulcerative lesion in a control group patient (conservative treatment). Both occurred following excessive Ablation Index applications (up to 460 and 480, respectively) with excessive contact force (30 g on average, with peaks up to 50 g). Six-months AF recurrence was not significantly different (10% in high power versus 8% in control, P=0.74). CONCLUSIONS: This randomized controlled study shows that a 45 W radiofrequency power CLOSE protocol in patients with paroxysmal AF significantly increases the global procedural efficiency with similar midterm efficacy. However, our study showed a narrower safety margin and a limited increased efficiency at the posterior wall using high power. This advocates against the use of high power in the region neighboring the esophagus.

Low contact force and force-time integral predict early recovery and dormant conduction revealed by adenosine after pulmonary vein isolation.

AIM: After pulmonary vein isolation (PVI), dormant conduction (DC) is present in at least one vein in a substantial number of patients. The present study seeks to determine whether there is a relationship between poor contact forces (CF) and the presence of DC after PVI. METHODS AND RESULTS: This prospective, operator-blinded, non-randomized dual-centre trial enrolled 34 consecutive patients with paroxysmal atrial fibrillation who were candidates for PVI. Radiofrequency (RF) energy was delivered by using an irrigated-tip force-sensing ablation catheter (Tacticath, St Jude Medical) at pre-defined target power. The operators were blinded to the CF data at all times. A total of 1476 RF applications were delivered in 743 pre-defined PV segments. For each application, the precise location of the catheter was registered and the following data were extracted from the Tacisys unit: application duration, minimum contact force, maximum contact force, average contact force (CF), and force-time integral (FTI). Sixty minutes after PVI, spontaneous early recovery (ER) of the left atrium (LA) to PV conduction was evaluated. In the absence of ER, the presence of a DC was evaluated by using intravenous adenosine (ATP). In the 34 patients recruited (23 males; mean age: 62 ± 9 years), all PVs were successfully isolated. At the end of the 60 min waiting period, 22 patients demonstrated at least one spontaneous ER or DC under ATP. The mean CF and FTI per PV segment differed significantly among the different veins but the sites of ER and DC were evenly distributed. However, both the minimum, the first and the mean CF and FTI per PV segment were significantly lower in the PV segments presenting either ER or DC as compared with those without ER or DC (mean CF: 4.9 ± 4.8 vs. 12.2 ± 1.65 g and mean FTI: 297 ± 291 vs. 860 ± 81 g s, P < 0.001 for both). Using multivariate analysis, both the mean CF and the FTI per lesion remained significantly associated with the risk of ER or DC. Moreover, a CF < 5 g per PV segment predicted ER+ and DC+ with a sensitivity of 71% and specificity of 82%. In contrast, ER and DC were very unlikely if RF application was performed with a mean CF > 10 g (negative predictive value: 98.7%). CONCLUSION: Both a low CF and a low FTI are associated with the ER of the PVI and DC after PVI.

Use of electroanatomic voltage mapping to guide lead implantation in young adults with congenital heart disease.

Lead implantation in young adults with congenital heart disease is often problematic due to the reduction in the number of surgical access routes and consequent scar tissue formation related to previous surgery. In such a situation, anatomic and electromagnetic voltage mapping of the heart may be useful to find the optimal implantation site for sensing and pacing activities.

Giant venous aneurysm jeopardising internal mammary arterial graft patency.

The authors report a 79-year old man with a history of coronary bypass surgery, presenting with acute heart failure and elevated troponin. Coronarography revealed a giant saphenous vein graft aneurysm, which was compressing the left internal mammary artery bypass graft. This was confirmed by a multislice enhanced-ECG gated cardiac CT, showing the venous aneurysm responsible for external compression of the arterial graft and its functional occlusion. Myocardial ischaemia, the mechanism leading to cardiac failure, was confirmed by hypoperfusion of the sub-endocardial area shown by the CT. The aneurysm was surgically removed without complications. The patient recovered and his cardiac function improved. This is the first recorded case of compression of the left internal mammary artery by an giant saphenous vein graft aneurysm having triggered severe myocardial ischaemia and heart failure. The authors review the incidence and complications of giant venous bypass graft aneurysms reported in the literature.

Intravenous adenosine to predict conduction recurrence in cavotricuspid isthmus early after ablation of typical atrial flutter: myth or reality?

INTRODUCTION: Early recovery of conduction (ER) after cavotricuspid isthmus (CTI) ablation for typical atrial flutter (AFl) occurs in approximately 10% of the patients. If not recognized, ER might lead to AFl recurrences. In this study, we hypothesized that intravenous adenosine (iADO) can be used to predict ER in the CTI immediately after RF ablation and distinguish functional block from the complete destruction of the CTI myocardium. METHODS: We prospectively included 68 consecutive patients (age: 65 ± 14 years; male: 78%) referred in our centers for AFl ablation. Immediately after bidirectional isthmus block validation, a bolus of iADO was given during continuous pacing from the proximal coronary sinus. Patients with functional block revealed under iADO (iADO+) and those without (iADO-) were subsequently observed for a 30-minute waiting period (ER-) or until sustained recovery of the conduction through the CTI (ER+). RESULTS: Seven patients presented a persistent recovery (ER+, 10.3%, mean time to recovery: 14 ± 9 minutes). None of them presented even a transient resumption of conduction under iADO (iADO+: 0). With univariate analysis, we identified a heavy patient weight (>95 kg) as a predictor of ER (sensitivity: 71%). CONCLUSIONS: Adenosine does not predict early recovery in the CTI after linear ablation for atrial flutter. We found that a patient weight over 95 kg predicted early recovery of conduction through the CTI with a sensitivity of 71%.

Relationship between transmural extent of necrosis and quantitative recovery of regional strains after revascularization.

OBJECTIVES: To better understand the quantitative relationship of recovery of regional and global dysfunction after revascularization in chronic infarcts with variable transmural extent of necrosis by delayed enhanced cardiac magnetic resonance. BACKGROUND: Studies relating transmurality of delayed enhanced magnetic resonance to functional recovery in dysfunctional myocardium using semiquantitative Likert scales have demonstrated the intermediate likelihood (50% probability) of recovery of dysfunction in subendocardial scars. METHODS: Forty-two patients with chronic left ventricular dysfunction due to coronary artery disease underwent tagged and delayed enhanced magnetic resonance before and 10 +/- 7 months after revascularization (coronary artery bypass graft: 35, percutaneous transluminal coronary angioplasty: 7). Left ventricular ejection fraction and regional mid-myocardial Eulerian radial thickening strain (Err) and mid-myocardial, subendocardial, and subepicardial Eulerian circumferential shortening strain (Ecc) strains were quantified in 16 segments per patient before and after revascularization and related to pre-operatively measured transmurality of necrosis. RESULTS: At baseline, 256 of 672 segments were dysfunctional, having <2 SD (i.e., >-10%) mid-myocardial Ecc. The magnitude of recovery of mid-myocardial Ecc (r = -0.33, p < 0.01) was inversely correlated with transmurality of necrosis before revascularization. Segments with <25% necrosis improved mid-myocardial Ecc and Err. No significant improvement of mid-myocardial Ecc or Err occurred when transmurality was > or =25%. However, subendocardial Ecc improved up to 75% transmural necrosis. Receiver-operator characteristic analysis determined optimal sensitivity (54%) and specificity (82%) for normalization of mid-myocardial Ecc (to <-10% Ecc) at a cutoff value of > or =18% transmural necrosis. Improvement of left ventricular ejection fraction (from 35 +/- 15% to 40 +/- 7%, p < 0.001) was best predicted (67% sensitivity, 58% specificity) by the presence of <4.5 dysfunctional segments with <75% transmural necrosis. CONCLUSIONS: The quantitative relationship between necrosis transmurality and improvement of regional and global dysfunction after revascularization is complex. Although improvement of recovery of regional mid-myocardial dysfunction after revascularization was observed only for scarring not exceeding 25% transmurality, global dysfunction significantly improved even when more extensive subendocardial scarring was revascularized.

Mechanisms of recurrent aortic regurgitation after aortic valve repair: predictive value of intraoperative transesophageal echocardiography.

OBJECTIVES: The aim of the present study was to examine the intraoperative echocardiographic features associated with recurrent severe aortic regurgitation (AR) after an aortic valve repair surgery. BACKGROUND: Surgical valve repair for AR has significant advantages over valve replacement, but little is known about the predictors and mechanisms of its failure. METHODS: We blindly reviewed all clinical, pre-operative, intraoperative, and follow-up transesophageal echocardiographic data of 186 consecutive patients who underwent valve repair for AR during a 10-year period and in whom intraoperative and follow-up echo data were available. After a median follow-up duration of 18 months, 41 patients had recurrent 3+ AR, 23 patients presented with residual 1+ to 2+ AR, and 122 had no or trivial AR. In patients with recurrent 3+ AR, the cause of recurrent AR was the rupture of a pericardial patch in 3 patients, a residual cusp prolapse in 26 patients, a restrictive cusp motion in 9 patients, an aortic dissection in 2 patients, and an infective endocarditis in 1 patient. RESULTS: Pre-operatively, all 3 groups were similar for aortic root dimensions and prevalence of bicuspid valve (overall 37%). Patients with recurrent AR were more likely to display Marfan syndrome or type 3 dysfunction pre-operatively. At the opposite end, patients with continent AR repair at follow-up were more likely to have type 2 dysfunction pre-operatively. After cardiopulmonary bypass, a shorter coaptation length, the degree of cusp billowing, a lower level of coaptation (relative to the annulus), a larger diameter of the aortic annulus and the sino-tubular junction, the presence of a residual AR, and the width of its vena contracta were associated with the presence of AR at follow-up. Multivariate Cox analysis identified a shorter coaptation length (odds ratio [OR]: 0.8, p = 0.05), a coaptation occurring below the level of the aortic annulus (OR: 7.9, p < 0.01), a larger aortic annulus (OR: 1.2, p = 0.01), and residual aortic regurgitation (OR: 5.3, p = 0.01) as risk factors of repair failure. CONCLUSIONS: Our results demonstrate that intraoperative transesophageal echocardiography can be used to identify patients undergoing AR repair who are at increased risk for late repair failure.

Early hazards of mitral ring annuloplasty in patients with moderate to severe ischemic mitral regurgitation undergoing coronary revascularization: the importance of preoperative myocardial viability.

BACKGROUND AND AIM OF THE STUDY: The impact of adding mitral ring annuloplasty (MRA) to coronary bypass grafting (CABG) in patients with ischemic mitral regurgitation (iMR) is unclear. The study aim was to compare the 30-day and four-year survival of patients with moderate to severe iMR undergoing CABG or CABG+MRA, and to investigate the role of contractile reserve (CR) in the prognostic response to MRA. METHODS: A total of 76 coronary patients (61 men, 15 women; mean age 62 +/- 9 years) with poor left ventricular ejection fraction (LVEF) of 33 +/- 11% and grade > or =2 iMR underwent low-dose dobutamine echocardiography to identify their CR before CABG. The survival of 34 patients undergoing CABG+MRA was compared to that of 42 patients who underwent CABG alone. The groups were further substratified according to their preoperative CR. RESULTS: During follow up, 24 patients died from cardiac causes, and two others required heart transplantation. At one year, the residual iMR and NYHA functional class were lower in patients undergoing MRA than in those that did not. The 30-day and four-year survivals were lower in patients undergoing MRA in the absence of CR than in the other patients (71 +/- 11% versus 95 +/- 3% at 30 days, p = 0.002; 35 +/- 11% versus 69 +/- 6% at four years, p = 0.008). Cox's proportional hazard analysis identified CR (HR = 0.14, 95% CI 0.05-0.38, p < 0.001), MRA (HR = 3.54, 95% CI 1.48-8.50, p = 0.004), additive EuroSCORE (HR = 1.29, 95% CI 1.08-1.55, p = 0.006) and LVEF (HR = 0.93, 95% CI 0.59-0.98, p = 0.001) as independent predictors of long-term outcome in this population. CONCLUSION: In patients with moderate to severe iMR, survival after CABG is mainly influenced by the presence of CR. By contrast, adding MRA to CABG does not affect long-term survival, except in patients without CR, in whom it increases early mortality.

Functional anatomy of aortic regurgitation: accuracy, prediction of surgical repairability, and outcome implications of transesophageal echocardiography.

BACKGROUND: For patients with aortic regurgitation (AR), aortic valve sparing or repair surgery is an attractive alternative to valve replacement. In this setting, accurate preoperative delineation of aortic valve pathology and potential repairability is of paramount importance. The aim of the present study was to assess the diagnostic value of preoperative transesophageal echocardiography (TEE) in defining the mechanisms of AR, as identified by surgical inspection, and in predicting repairability, by using the final surgical approach as reference. METHODS AND RESULTS: One hundred and sixty-three consecutive patients (117 males, mean age: 58+/-14 years) undergoing AR surgery were included. Mechanisms of AR were categorized by TEE and surgical inspection as follows: type 1, aortic dilatation; type 2, cusp prolapse; and type 3, restrictive cusp motion or endocarditis. At surgery, mechanisms of AR were type 1 in 41 patients, type 2 in 62, and type 3 in 60. Agreement between TEE and surgical inspection was 93% (kappa=0.90). Valve sparing or repair was performed in 125 patients and valve replacement in 38 patients. TEE correctly predicted the final surgical approach in 108/125 (86%) patients undergoing repair and in 35/38 (93%) patients undergoing replacement. The gross anatomic classification of AR lesions by TEE was determinant of valve repairability and postoperative outcome (4-year freedom from > grade 2 AR, reoperation, or death, P=0.04). CONCLUSIONS: TEE provides a highly accurate anatomic assessment of all types of AR lesions. In addition, the functional anatomy of AR defined by TEE is strongly and independently predictive of valve repairability and postoperative outcome.

Aortic valve area assessment: multidetector CT compared with cine MR imaging and transthoracic and transesophageal echocardiography.

PURPOSE: To prospectively compare the accuracy of multidetector computed tomographic (CT) measurements of the aortic valve area (AVA) with transesophageal echocardiography (TEE) and cine magnetic resonance (MR) measurements of this area for preoperative examination of patients undergoing cardiac surgery, with transthoracic echocardiography (TTE) as the reference standard. MATERIALS AND METHODS: After giving informed consent for the institutional review board-approved study protocol, 48 patients (33 men, 15 women; mean age, 62 years+/-13 [standard deviation]) with (n=27) or without (n=21) aortic stenosis underwent multidetector CT, cine MR, TTE, and TEE before undergoing cardiac surgery. AVAs derived with manual planimetry by using cine short-axis multidetector CT, MR, and TEE images obtained through the aortic valve were compared among each other and with AVAs measured by using continuity equation TTE at regression and Bland-Altman analyses. The diagnostic accuracy of multidetector CT for detection of aortic stenosis was compared with that of TTE by using kappa statistics and receiver operating characteristic curves. RESULTS: Multidetector CT-derived AVA correlated highly with MR-derived (r=0.98, P<.001), TEE-derived (r=0.98, P<.001), and TTE-derived (r=0.96, P<.001) AVA. Multidetector CT planimetry AVAs (mean AVA+/-standard deviation, 2.5 cm2+/-1.7) were not significantly different from MR planimetry (2.4 cm2+/-1.8, P>.99) or TEE planimetery (2.5 cm2+/-1.7, P=.21) AVAs, but they were significantly larger than TTE-derived AVAs (2.0 cm2+/-1.5, P<.001). With TTE as the reference standard, multidetector CT correctly (kappa=0.88, P<.001) depicted all 21 normal, six of eight mildly stenotic (AVA>or=1.2 cm2 and <2.0 cm2), seven of eight moderately stenotic (AVA>or= 0.8 cm2 and <1.2 cm2), and 10 of 11 severely stenotic (AVA<0.8 cm2) valves. It also correctly depicted all 14 bicuspid valves identified with TEE, eight of which were missed with TTE. CONCLUSION: Multidetector CT enables accurate noninvasive assessment of the AVA.

Usefulness of 40-slice multidetector row computed tomography to detect coronary disease in patients prior to cardiac valve surgery.

Preoperative identification of significant coronary artery disease (CAD) in patients prior to valve surgery requires systematic invasive coronary angiography. The purpose of this current prospective study was to evaluate whether exclusion of CAD by multi-detector CT (MDCT) might potentially avoid systematic cardiac catheterization in these patients. Eighty-two patients (53 males, 62 +/- 13 years) scheduled to undergo valve surgery underwent 40-slice MDCT before invasive quantitative coronary angiography (QCA). According to QCA, 15 patients had CAD (5 one-vessel, 6 two-vessel and 4 three-vessel disease). The remaining 67 patients had no CAD. On a per-vessel basis, MDCT correctly identified 27/29 (sensitivity 93%) vessels with and excluded 277/299 vessels (specificity 93%) without CAD. On a per-patient basis, MDCT correctly identified 14/15 patients with (sensitivity 93%) and 60/67 patients without CAD (specificity 90%). Positive and negative predictive values of MDCT were 67% and 98%. Performing invasive angiography only in patients with abnormal MDCT might have avoided QCA in 60/82 (73%). MDCT could be potentially useful in the preoperative evaluation of patients with valve disease. By selecting only those patients with coronary lesions to undergo invasive coronary angiography, it could avoid cardiac catheterization in a large number of patients without CAD.