Dimitar Divchev

Predictive factors for pacemaker requirement after transcatheter aortic valve implantation

BackgroundTranscatheter aortic valve implantation (TAVI) has been established as a treatment option for inoperable patients with symptomatic aortic valve stenosis. However, patients suffer frequently from conduction disturbances after TAVI.MethodsBaseline, procedural as well as surface and intracardiac ECG parameters were evaluated for patients treated with TAVI and a comparison between patients requiring pacemaker with those not suffering from relevant conduction disorders were done.ResultsTAVI was successfully in all patients (n=45). Baseline surface and intracardiac ECG recording revealed longer PQ (197.1±51.2 msec versus 154.1±32.1 msec; p<0.001), longer AH (153.6±43.4 msec versus 116.1±31.2 msec; p<0.001) and HV interval (81.7±17.8 msec versus 56.8±8.5 msec; p<0.001) in patients with need for a pacemaker (n=23) versus control group (n=22); furthermore, 7-day follow-up analysis showed a higher prevalence of new left bundle branch block (LBBB) (87.0% versus 31.9%; p<0.001). Multivariate analysis revealed that only new LBBB, QRS duration >120 msec and a PQ interval >200 msec immediately (within 60 minutes) after implantation of the aortic valve were predictors for high-grade (type II second-degree and third-degree) AV block. Other clinical parameters as well as baseline electrocardiographic parameters had no impact on critical conduction delay.ConclusionCardiac conduction disturbances are common after TAVI. The need for pacing after TAVI is predictable by surface ECG evaluation immediately (within 60 minutes) after the procedure.

Early and mid-term outcomes of percutaneous mitral valve repair with the MitraClip®: comparative analysis of different EuroSCORE strata

AIMS Compare mid-term outcomes after MitraClip® implantation for severe mitral regurgitation (MR) in patients categorised in different logistic EuroSCORE (LES) groups. METHODS AND RESULTS MitraClip was implanted in 85 patients (78 ± 6 years, 48 men [56.5%]) with severe symptomatic MR. Baseline characteristics, perioperative results, mid-term survival, major adverse cerebrovascular and cardiac events (MACCE), and re-hospitalisation were compared in patients with LES <20% (n=30) and ≥ 20% (n=55). Overall LES was 24 ± 12 (range 2.5-56.3) and STS-score 12 ± 7 (range 1.2-31.2). Overall procedural success rate was 96.5% with an in-hospital mortality rate of 3.5%. Echocardiographic and clinical follow-up confirmed similar mean transmitral pressure gradient (p=0.13), MR degree (p=0.48), and NYHA Class (p=0.93). Estimated six-month survival and freedom from composite endpoint was 80.7%/77.1% in LES ≥ 20% and 90.8/86.6% in LES<20% group, respectively (p= 0.014; p=0.018). Multivariate analysis determined LES ≥ 20% (OR=8.1; 95% CI 1.002-65.186), mean transmitral gradient after intervention (OR 2.5; 95% CI 1.267-5.131) and residual MR (OR=5.1; 95% CI 1.464-17.946) as predictors for overall mortality. CONCLUSIONS LES is a good predictor of perioperative results, and follow-up adverse outcomes after MitraClip implantation are significantly influenced by the preoperative risk profile. The presence of residual MR immediately after MitraClip therapy can exacerbate the occurrence of MACCE.

Early and late management of type B aortic dissection

The management of type B aortic dissection is undergoing profound changes with timely TEVAR accepted as first-line strategy in the setting of complicated dissection; with recent technological advances and in experienced hands this intervention is considered safe and life-saving. With the ability to remodel the dissected aorta as a result of scaffolding even pre-emptive endovascular treatment is being considered and supported by long-term stability and often prevention of aneurysmal expansion. This insight and a growing number of silent risk conditions (resistant hypertension, partial false lumen thrombosis) may lower the threshold for TEVAR in asymptomatic patients in the subacute phase. In the chronic phase of a type B dissection patients are usually free of symptoms, however, with the expanding false lumen at risk of rupture. Advanced TEVAR options (including branches and fenestrations) are likely to be used more often than open surgical replacement of such aneurysmatic segment of the dissected aorta in that chronic phase. All dissection patients should be offered lifelong surveillance.

Percutaneous mitral valve repair with the mitraclip® system

Objectives: The purpose of this study was to compare outcomes using standard clipping (SC) (one to two clips) or multiple clipping (MC) (more than two clips). Background: MitraClip® implantation using MC has been proposed to treat severe mitral regurgitation (MR) in high‐risk patients. Methods and Results: A tailored strategy was used implanting as many clips as required to eliminate MR. A total of 85 consecutive patients [78 ± 6 years, 48 men (56.5%) ] with MR (grade 3+ or 4+) were included. EuroSCORE was 24 ± 12 (2.5–56.3) and STS‐score 12 ± 7 (1.2–31.2). SC was used in 61 (71.8%) and MC in 24 (28.2%) patients. Patients in MC group had larger mitral valve (MV) annuli (P = 0.025), MV orifice areas (MVOA) (P = 0.01), and MR degree (P = 0.005). Successful clip placement was achieved in 82 patients (96.5%). At discharge, no patient had grade 4+ MR. MR 3+ presented in 4 patients (7.0%) in the SC group and in 1 (4.5%) in the MC group (P = 0.72). There were 3 (3.5%) in‐hospital deaths. Follow up (211 ± 173 days, range 4–652) echocardiography confirmed similar MVOA (P = 0.83) and MV gradients (P = 0.54) in the both groups. At linear regression there was no independent correlation between clips number and postoperative MVOA/gradient. One‐year survival was 71.1% without difference between groups (P = 0.74). Conclusion: Although the hemodynamic and anatomical basis of MR may differ, every procedure should aim at eliminating MR. In some patients this goal can be achieved using MC with minimized risk of MV stenosis if preoperative anatomy/mechanism of MV regurgitation are adequately assessed.

Morbidity and mortality of nonagenarians undergoing CoreValve implantation

BackgroundNonagenarians are mostly denied from different therapeutic strategies due to high comorbidity index and risk-benefit calculation. We present the results of nonagenarians with high comorbidity index not eligible for conventional aortic valve surgery undergoing transcatheter aortic valve implantation (TAVI) with the CoreValve system.MethodsOur retrospective analysis include baseline parameters, procedural characteristics, morbidity, mortality as well as twelve-lead surface ECG and echocardiographic parameters which were revealed preinterventionally, at hospital discharge and at 30-day follow-up. Clinical follow-up was performed 6 months after TAVI.ResultsOut of 158 patients 11 nonagenarians with a mean age of 92.6 ± 1.3 years suffering from severe aortic valve stenosis and elevated comorbidity index (logistic EuroSCORE of 32.0 ± 9.5%, STS score 25.3 ± 9.7%) underwent TAVI between January 2008 and January 2011 using the third-generation percutaneous self-expanding CoreValve prosthesis. Baseline transthoracic echocardiography reported a mean aortic valve area (AVA) of 0.6 ± 0.2 cm2 with a mean and peak pressure gradient of 60.2 ± 13.1mmHg and 91.0 ± 27.4mmHg, respectively. The 30-day follow up all cause and cardiovascular mortality was 27.3% and 9.1%, respectively. One major stroke (9.1%), 2 pulmonary embolisms (18.2%), 1 periprocedural (9.1%) and 1 (9.1%) spontaneous myocardial infarction occured. Life-threatening or disabling bleeding occurred in 2 cases (18.2%), and minor bleeding in 7 cases (63.6%). Mean severity of heart failure according to NYHA functional class improved from 3.2 ± 0.8 to 1.36 ± 0.5 while mean AVA increased from 0.6 ± 0.2cm2 to 1.8 ± 0.2cm2. At 6-months follow-up 8 patients (72.7%) were alive without any additional myocardial infarction, pulmonary embolism, bleeding, or stroke as compared to 30-day follow-up.ConclusionOur case series demonstrate that even with elevated comorbidity index, clinical endpoints and valve-associated results are relatively favorable in nonagenarians treated with CoreValve.

Cardiac troponin T and echocardiographic dimensions after repeated sprint vs. moderate intensity continuous exercise in healthy young males.

Regular physical exercise can positively influence cardiac function; however, investigations have shown an increase of myocardial damage biomarkers after acute prolonged endurance exercises. We investigated the effect of repeated sprint vs. moderate long duration exercise on markers of myocardial necrosis, as well as cardiac dimensions and functions. Thirteen healthy males performed two different running sessions (randomized, single blinded cross-over design): 60 minutes moderate intensity continuous training (MCT, at 70% of peak heart rate (HRpeak)) and two series of 12 × 30-second sprints with set recovery periods in-between (RST, at 90% HRpeak). Venous blood samples for cardiac troponin T (cTnT), creatine kinase (CK) and MB isoenzyme (CK-MB) were taken 1 and 4 hours after exercise sessions. After each session electrocardiographic (ECG) and transthoracic echocardiographic (TTE) data were recorded. Results showed that all variables - average heart rate, serum lactate concentration during RST, subjective exertion and cTnT after RST - were significantly higher compared to MCT. CK and CK-MB significantly increased regardless of exercise protocol, while ECG and TTE indicated normal cardiac function. Our results provide evidence that RST contributes significantly to cTnT and CK release. This biomarker increase seems to reflect a physiological rather than a pathological phenomenon in healthy, exercising subjects.

Percutaneous mitral valve repair with the MitraClip system: perioperative and 1-year follow-up results using standard or multiple clipping strategy.

Objectives: The purpose of this study was to compare outcomes using standard clipping (SC) (one to two clips) or multiple clipping (MC) (more than two clips). Background: MitraClip® implantation using MC has been proposed to treat severe mitral regurgitation (MR) in high‐risk patients. Methods and Results: A tailored strategy was used implanting as many clips as required to eliminate MR. A total of 85 consecutive patients [78 ± 6 years, 48 men (56.5%) ] with MR (grade 3+ or 4+) were included. EuroSCORE was 24 ± 12 (2.5–56.3) and STS‐score 12 ± 7 (1.2–31.2). SC was used in 61 (71.8%) and MC in 24 (28.2%) patients. Patients in MC group had larger mitral valve (MV) annuli (P = 0.025), MV orifice areas (MVOA) (P = 0.01), and MR degree (P = 0.005). Successful clip placement was achieved in 82 patients (96.5%). At discharge, no patient had grade 4+ MR. MR 3+ presented in 4 patients (7.0%) in the SC group and in 1 (4.5%) in the MC group (P = 0.72). There were 3 (3.5%) in‐hospital deaths. Follow up (211 ± 173 days, range 4–652) echocardiography confirmed similar MVOA (P = 0.83) and MV gradients (P = 0.54) in the both groups. At linear regression there was no independent correlation between clips number and postoperative MVOA/gradient. One‐year survival was 71.1% without difference between groups (P = 0.74). Conclusion: Although the hemodynamic and anatomical basis of MR may differ, every procedure should aim at eliminating MR. In some patients this goal can be achieved using MC with minimized risk of MV stenosis if preoperative anatomy/mechanism of MV regurgitation are adequately assessed.

Renal Sympathetic Denervation in Patients with Aortic Dissection

BACKGROUND We report on feasibility, safety, and mid-term outcomes of renal sympathetic denervation (RSD) in hypertensive patients after endovascular treatment for aortic dissection. METHODS Six patients were subjected to RSD after receiving endovascular treatment for complicated aortic dissection. Between April 2011 and May 2012, RSD procedure was applied for persistent hypertension despite maximized antihypertensive drug therapy using the Symplicity® catheter system. Endovascular aortic treatment was performed for malperfusion or rapid expansion by virtue of a stent-graft system (Valiant®, n = 5) or an open cell stent (Smart®; n = 1). RESULTS Systolic blood pressure (BP) was 189.8 ± 32.2 mmHg and diastolic BP 96.2 ± 11.1 mmHg at baseline on 24 hours readings; after RSD, a successful reduction to 129.5 ± 11.8 mmHg (P = 0.004) for systolic and to 77.7 ± 10.7 (P = 0.004) for diastolic BP at 3-month follow-up was documented on ambulatory 24-hour BP readings with sustained reduction at 1-year follow-up (127.2 ± 11.8 mmHg [P = 0.002] and 77.7 ± 7.7 [P = 0.011]). CONCLUSION RSD using the Symplicity® catheter system is feasible and safe in hypertensive patients previously subjected to endovascular repair for complicated aortic dissection.

A multicentre European registry to evaluate the Direct Flow Medical transcatheter aortic valve system for the treatment of patients with severe aortic stenosis

AIMS Our aim was to assess the clinical outcomes of the Direct Flow Medical Transcatheter Aortic Valve System (DFM-TAVS), when used in routine clinical practice. METHODS AND RESULTS This is a prospective, open-label, multicentre, post-market registry of patients treated with DFM-TAVS according to approved commercial indications. Echocardiographic and angiographic data were evaluated by an independent core laboratory and adverse events were adjudicated and classified according to VARC-2 criteria by an independent clinical events committee. The primary endpoint was freedom from all-cause mortality at 30 days post procedure. Secondary endpoints included procedural, early safety and efficacy endpoints at 30 days. Two hundred and fifty patients with severe aortic stenosis undergoing transcatheter aortic valve implantation (TAVI) with the DFM-TAVS were enrolled in 21 European centres. The primary endpoint, freedom from all-cause mortality at 30 days, was met in 98% (245/250) of patients. Device success was 83.8%. Moderate or severe aortic regurgitation was reported in 3% of patients, and none/trace regurgitation in 73% of patients. Post-procedural permanent pacemaker implantation was performed in 30 patients (12.0%). CONCLUSIONS The DFM-TAVS was associated with good short-term outcomes in this real-world registry. The low pacemaker and aortic regurgitation rates confirm the advantages of this next-generation transcatheter heart valve (THV).

Predicting long-term outcomes of acute aortic dissection: a focus on gender

Acute aortic disease ranks as the 19th leading cause of death with steadily increasing incidence. The prevalence of aneurysms varies depending on the localization along the aorta with a mortality of aortic rupture of around 80%. Traditionally, aortic disease affects men more frequently than women, however, with a varying gender ratio. Nevertheless, in the setting of acute aortic dissection, the International Registry of Acute Aortic Dissections identified significant gender-related differences in the management of both sexes with acute aortic conditions. Current data suggest that women are at an increased risk of both dying from aortic dissection and having aorta-related complications than men. This review aims to report on current evidence of gender impact on natural history, treatment and outcomes in patients with acute aortic dissection.