Electroanatomic visualization of coronary arteries: a case series to elicit safety, feasibility, and diagnostic value in complex ablation procedures.

AIMS: The goal of this case series was to evaluate the feasibility, safety, and advantages of a wire-based approach for the live visualization of coronary arteries (CAs) in an electroanatomic mapping (EAM) system and to assess its diagnostic information. METHODS AND RESULTS: For this single-centre case series, we included procedures in which close proximity of a possible ablation site to any epicardial vessel was suspected. An uncoated-tip guidewire was introduced into the relevant CAs after exclusion of critical CA stenosis by coronary angiography. By connecting this wire to the EAM system using a clip and pin connection, mapping and live visualization of the wire tip is possible, as well as the assessment of the local electrograms within the respective CAs. Procedural wire insertion and intracoronary mapping was performed by EP specialists and was assisted to judge the relevance of CA disease by an interventional cardiologist. A total of nine procedures in nine patients were included in this case series, four ventricular tachycardia ablation procedures and five procedures for the ablation of premature ventricular contractions. The left CAs were mapped in eight cases and the right CA was mapped in one case. In two cases, epicardial mapping was combined with visualization of the right or left CAs. There were no complications attributed to coronary wiring and mapping in this case. CONCLUSION: We demonstrated the feasibility and safety of CA visualization and integration in an EAM. The live visualization of the CAs added valuable information without the need for preprocedural planning or the purchase of separate software. Electroanatomic visualization was achieved intraprocedurally in a safe and straightforward manner, adding critical diagnostic information without excessive costs or risks.

Left Atrial Fibrosis after Single Shot Guided Pulmonary Vein Isolation.

Cryoballoon (CB)-based pulmonary vein isolation (PVI) is an effective treatment modality for patients with atrial fibrillation (AF) with encouraging acute and long-term outcome data. However, the size of collaterally created lesion sets adjacent to the pulmonary veins (PVs) remains unclear, especially when CB ablation is performed with individualized time-to-isolation (TTI) protocols. This study seeks to investigate the extension of lesions at the posterior wall and the roof of the left atrium (LA). Thirty patients with paroxysmal or persistent AF underwent ablation with a fourth-generation CB. The individual freeze-cycle duration was set at TTI + 120 s. A total of 120 PVs were identified, and all were successfully isolated. A three-dimensional electroanatomical high-density (HD) mapping of the LA was performed in every patient before and after PVI. The surface areas of the posterior wall and LA roof were measured and compared with lesion extension after PVI. After CB ablation, 65.6 ± 16.9% of the posterior wall and 75.4 ± 18.4% of the LA roof remained unablated. In addition, non-antral lesion formation was observed in every patient in at least one PV. After CB ablation, anterior antral parts of the superior PVs showed the greatest unablated areas compared with the other antral areas. HD re-mapping after CB-based PVI demonstrated that major regions of the posterior wall and roof remained electrically normal and unaffected. Unablated antral areas were localized predominantly in the anterior segments of the superior PVs and may be partly responsible for AF recurrence.

[Localization of ventricular premature contractions by 12-lead ECG]. / Lokalisation ventrikulärer Extrasystolen im 12-Kanal-EKG.

The advances in imaging and 3D mapping systems in the last decade allowed a better correlation of ventricular premature contractions (PVCs) with anatomical structures. With regard to PVCs, interpretation of the 12-lead ECG is still crucial for the management of patients and the planning of therapies. Although there is an armamentarium of indices and algorithms to exactly pinpoint the origin of a PVC in advance, a thorough understanding of cardiac anatomy and impulse propagation, together with an awareness of the surface ECGs limitations, provides a sufficiently close approximation. PVCs from the diaphragmatic part of the ventricular cavae exhibit a superiorly directed axis, whereas PVCs from superior parts of the heart show an inferior axis. A right bundle branch block morphology or positive concordance of the precordial leads yields a high probability of left ventricular origin of a PVC. A left bundle branch block morphology is indicative of a right ventricular or septal origin of a PVC. Using the transition zone, one can estimate the origin of a PVC with regard to anterior or posterior regions of the heart: A late precordial transition is indicative of a right ventricular origin, an early precordial transition suggests a left ventricular focus. An absent transition in the sense of negative concordance is indicative for an apical origin. The intertwined course of the ventricular outflow tracts makes PVC localization more difficult. Here, shape and height of the R­wave in V1-V3 help to narrow the origin down. PVCs from structures like the papillary muscles, the moderator band or infundibular bands are challenging to interpret and evidence of the limitations of the surface ECG. Based on the information gained by the aforementioned approach, a prediction of prognosis and possible treatment success is possible.

Myocardial Fibrosis Predicts 10-Year Survival in Patients Undergoing Aortic Valve Replacement.

Background Long-term data on evolution and clinical impact of myocardial fibrosis in valvular heart disease are scarce. Methods and Results In this 10 years' extension of a prospective study in patients undergoing conventional aortic valve replacement because of symptomatic severe aortic valve stenosis, the impact of myocardial replacement fibrosis (MRF) on long-term outcome was assessed. Endomyocardial biopsies were acquired during aortic valve replacement in 58 consecutive patients. MRF was graded using the calculated percentage area of fibrosis and patients categorized as severe (n=21), mild (n=15), and no fibrosis (n=22). Echocardiography including strain imaging, as well as cardiovascular magnetic resonance, to assess late gadolinium enhancement was performed at baseline, 1, and 10 years after aortic valve replacement. Death of any cause occurred in 21 patients (38.9%): 3 (14.3%) in the group without MRF, 6 (42.9%) in the mild MRF group, and 12 (63.2%) in the severe MRF group ( P=0.006), resulting in the lowest cumulative survival for patients with severe MRF (log-rank P=0.003). In the group without MRF, none died of cardiovascular cause. MRF was found to be an independent predictor of survival (hazard ratio, 1.271; 95% CI, 1.032-1.564; P=0.024). Conclusions This 10-year follow-up study underlines the profound impact of replacement fibrosis with regard to cardiac and all-cause mortality in patients undergoing aortic valve replacement for severe aortic valve stenosis. Integrating cardiovascular magnetic resonance and echocardiographic functional imaging beyond ejection fraction quantification could help in clinical decision making to stratify patient prognosis with regard to myocardial longitudinal function and prevalence of replacement fibrosis.

Role of Global Longitudinal Strain in the Prediction of Outcome in Patients With Severe Aortic Valve Stenosis.

In the present study, we assessed the role of Global Longitudinal Strain (GLS) as a predictor of all-cause mortality in patients with severe aortic valve stenosis (AS), irrespective of their type of treatment. Data of 807 patients with AS receiving complete echocardiographic and clinical examination were retrospectively analyzed. Valve area <1 cm2 and sufficient image quality were inclusion criteria; patients with severe concomitant valvulopathy were excluded. Patients were grouped into treatment (aortic valve replacement [AVR]) and conservative (non-AVR) groups. Multivariable Cox analysis was used to assess predictors of all-cause mortality. Five hundred fourteen patients were included and 53.3% were of male gender. Mean age at inclusion was 76.4 ± 9.8 years; 326 received AVR. Death from any cause occurred in 72.9% of non-AVR group and 17.8% of AVR group (p <0.001). GLS (expressed as |%|) was found to be an independent predictor of all-cause mortality in non-AVR group (hazard ratio [HR] 0.933, 95% CI 0.854 to 0.987, p = 0.038). In patients receiving AVR, GLS and history of coronary artery bypass graft were found to be independent predictors of all-cause mortality (HR for GLS 0.912, 95% CI 0.730 to 0.999, p = 0.048; HR for coronary artery bypass graft 2.977, 95% CI 1.014 to 6.273, p = 0.013). In non-AVR patients, GLS <9.7% showed a higher 1- and 5-year mortality (log rank p values of 0.002 and 0.010, respectively). In conclusion, GLS is an independent predictor of all-cause mortality in severe AS, irrespective of their type of treatment. GLS <9.7% indicates a significantly higher 1- and 5-year mortality in non-AVR patients. Therefore, GLS should be regularly assessed for enhanced risk stratification and clinical decision-making.

Differences in natural history of low- and high-gradient aortic stenosis from nonsevere to severe stage of the disease.

BACKGROUND: The aim of the present study was to assess and compare the disease progression of aortic stenosis (AS) subtypes from nonsevere to severe disease on the basis of measures of gradient and flow. METHODS: Seventy-seven patients with AS (mean aortic valve area, 1.3 ± 0.3 cm(2) at baseline) underwent echocardiographic examination, including two-dimensional speckle-tracking strain measurements. Patients were retrospectively grouped according to mean transvalvular pressure gradient (40 mm Hg) into low-gradient (LG/AS) and high-gradient (HG/AS) groups. The LG/AS group was further subdivided into low-flow (LF/LG; i.e., stroke volume index < 35 mL/m(2)) and normal-flow (NF/LG) groups. For subanalysis, the LF/LG group was split into two groups: "paradoxical" (P-LF/LG; ejection fraction > 50%) and "classical" LF/LG (C-LF/LG; ejection fraction < 50%). Follow-up echocardiography was performed in patients with severe AS after 3.3 ± 1.7 years. Survival status was ascertained after 5.0 ± 2.0 years. RESULTS: Coronary artery disease was more frequent in LG/AS than HG/AS patients. Already at baseline, LF/LG patients showed reduced left ventricular global systolic strain and reduced systemic arterial compliance compared with HG/AS patients (HG/AS, 1.0 ± 0.4 mL · mm Hg-(1) · m(-2); NF/LG, 0.9 ± 0.2 mL · mm Hg-(1) · m(-2); LF/LG, 0.6 ± 0.2 mL · mm Hg(-1) · m(-2); P < .001). The initially elevated valvuloarterial impedance increased significantly more in LG/AS than in the other groups (HG/AS, 2.2 ± 0.9 mm Hg · mL-(1) · m(-2); NF/LG, 2.2 ± 0.5 mm Hg · mL-(1) · m(-2); LF/LG, 3.2 ± 0.8 mm Hg · mL(-1) · m-(2); P < .001), while aortic valve area decreased by 42% in HG/AS versus 34% in NF/LG and 32% in LF/LG (P < .001). At follow-up, global systolic strain was significantly reduced in C-LF/LG (7.7 ± 2.5 vs 13.5 ± 2.9 in P-LF/LG, P < .001). In P-LF/LG, mitral E/E' ratio increased significantly from 8.9 ± 4.0 to 26.4 ± 9.2 (P < .05). CONCLUSIONS: In patients with AS with high-gradient physiology, the valve constitutes the primary problem. By contrast, low-gradient AS is a systemic disease with valvular, vascular, and myocardial components, resulting in a slower progression of transvalvular gradient, but worse clinical outcome. In C-LF/LG, impaired systolic function leads to an LG flow pattern, whereas the pathophysiology in P-LF/LG is predominantly a diastolic dysfunction.