RESUMO
[Figure: see text].
Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Ablação por Cateter/efeitos adversos , Frequência Cardíaca/fisiologia , Síndrome do Nó Sinusal/cirurgia , Cirurgia Assistida por Computador/métodos , Síncope Vasovagal/fisiopatologia , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Idoso , Ablação por Cateter/métodos , Feminino , Seguimentos , Sistema de Condução Cardíaco/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Prospectivos , Síndrome do Nó Sinusal/diagnóstico , Síndrome do Nó Sinusal/fisiopatologia , Síncope Vasovagal/etiologia , Fatores de Tempo , Adulto JovemRESUMO
Background Biatrial, extensive, and complex ablation strategies have been published for the treatment of neurally mediated syncope, sinus node dysfunction, and functional atrioventricular block. We have developed a less extensive and more specific approach compared with previously published cardioneuroablation strategies, called cardio-neuromodulation. It is based on tailored vagolysis of the sinoatrial node through partial ablation of the anterior right-ganglionated plexus, preferentially through a right-sided approach. Methods Patients with syncope were enrolled between December 2016 and December 2017. They were assigned to group A if they had a positive head-up tilt test and to group B if they presented with a pause ≥3 seconds. The area to target during cardio-neuromodulation was designed offline on a computed tomographic scan. Slow heart rates and pauses were compared during 24-hour rhythm registration at baseline, at 1-month follow-up, and 6-month follow-up. Syncope burden was assessed before the procedure and at 3- and 6-month follow-up. Results Twenty patients underwent cardio-neuromodulation through a right-sided approach (12 in group A, 8 in group B). The first application of radiofrequency energy led to a P-P interval shortening >120 ms in all 20 patients. After a mean±SD ablation time of 7±4 minutes and mean ablated surface area of 11±6 mm2, the P-P interval shortened by 219±160 ms ( P<0.001). The number of beats <50/min during 24-hour rhythm registration was reduced by a median of 100% at 6-month follow-up ( P<0.001). Syncope burden was reduced by 95% at 6-month follow-up ( P<0.001). Conclusions These data indicate that cardio-neuromodulation, through a right-sided and computed tomographic-guided procedure, is safe, fast, and highly reproducible in preventing inappropriate functional sinus bradycardia and syncope recurrence.
Assuntos
Ablação por Cateter/métodos , Radiografia Intervencionista/métodos , Síndrome do Nó Sinusal/cirurgia , Síncope Vasovagal/etiologia , Tomografia Computadorizada por Raios X , Potenciais de Ação , Adulto , Idoso , Bélgica , Bradicardia/etiologia , Bradicardia/fisiopatologia , Ablação por Cateter/efeitos adversos , Eletrocardiografia Ambulatorial , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Síndrome do Nó Sinusal/complicações , Síndrome do Nó Sinusal/diagnóstico , Síndrome do Nó Sinusal/fisiopatologia , Síncope Vasovagal/diagnóstico , Síncope Vasovagal/fisiopatologia , Teste da Mesa Inclinada , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
AIMS: Rotational angiography with digital three-dimensional reconstruction (3DRA) allows per-procedural 3D imaging to facilitate cardiac ablation procedures. We developed a new approach that allows per-procedural 3D imaging of the atria and ventricles with a single C-arm rotation, combining higher 3D image quality with a lower contrast and radiation dose. METHODS AND RESULTS: Forty patients underwent 3DRA of the left atrium (LA, n = 26), right atrium (RA, n = 11), left ventricle (LV, n = 2), or right ventricle (RV, n = 1) during ablation procedures performed under general anaesthesia. Contrast agent (60 +/- 12 mL) was diluted and injected directly in the chamber of interest, during adenosine-induced ventricular asystole (n = 31) or rapid RV pacing (n = 9, atrial imaging only) to reduce cardiac motion artefacts and enhance contrast opacification during rotational imaging. Reconstructed 3D data sets were graded according to predefined quality criteria (n = 40) and quantitatively compared with cardiac computed tomography (CT) (LA, n = 14). Adenosine-induced ventricular asystole and rapid pacing both allowed a sustained and homogeneous contrast opacification of target cardiac chambers, resulting in useful 3D data sets in 39 of 40 (98%) patients. Moreover, it was possible to achieve 'good' or 'optimal' 3D image quality in the majority of patients (adenosine: 61%, pacing 78%, P = 0.69). When compared with rapid pacing, the total elimination of cardiac motion artefacts with adenosine more frequently resulted in 'optimal' 3D image quality (42% vs. 11%, P = 0.01) and added the possibility for single-rotation 3D imaging of the ventricles. Quantitative analysis showed an excellent agreement between pulmonary vein diameters measured on cardiac CT and 3DRA images. Integration of 3DRA-based LA surfaces with real-time fluoroscopy was easy and highly accurate. CONCLUSION: Adenosine-induced ventricular asystole or rapid ventricular pacing allow acquisition of 3DRA with an excellent direct contrast opacification of any cardiac chamber and a reduction of cardiac motion artefacts, resulting in high-quality per-procedural 3D imaging with a single C-arm rotation.
Assuntos
Adenosina , Procedimentos Cirúrgicos Cardiovasculares/métodos , Imageamento Tridimensional/métodos , Cirurgia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Fibrilação Ventricular/diagnóstico por imagem , Fibrilação Ventricular/cirurgia , Feminino , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Integração de Sistemas , Resultado do TratamentoRESUMO
BACKGROUND: It has been proposed that the highest risk for cardiac events in patients with long-QT syndrome subtype 2 (LQT2) is related to mutations in the pore region of the KCNH2 channel. It has also been suggested that a subpopulation of LQT2 patients may benefit from pharmacological therapy with modified KCNH2 channel-blocking drugs. METHODS AND RESULTS: In a large LQT2 family (n=33), we have identified a novel nonpore missense mutation (K28E) in the Per-Arnt-Sim (PAS) domain of the KCNH2 channel associated with a malignant phenotype: One third of the suspected gene carriers experienced a major cardiac event. Wild-type and K28E-KCNH2 channels were transiently transfected in HEK293 cells. For the mutant channel, whole-cell patch-clamp analysis showed a reduced current density, a negative shift of voltage-dependent channel availability, and an increased rate of deactivation. Western blot analysis and confocal imaging revealed a trafficking deficiency for the mutant channel that could be rescued by the K+ channel blocker E-4031. In cells containing both wild-type and mutant channels, deactivation kinetics were normal. In these cells, reduced current density was restored with E-4031. CONCLUSIONS: Our data suggest that besides pore mutations, mutations in the PAS domain may also exhibit a malignant outcome. Pharmacological restoration of current density is promising as a mutation-specific therapy for patients carrying this trafficking-defective mutant.