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2.
Circ Arrhythm Electrophysiol ; 13(1): e007611, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31922914

RESUMO

BACKGROUND: Data characterizing structural changes of arrhythmogenic right ventricular (RV) cardiomyopathy are limited. METHODS: Patients presenting with left bundle branch block ventricular tachycardia in the setting of arrhythmogenic RV cardiomyopathy with procedures separated by at least 9 months were included. RESULTS: Nineteen consecutive patients (84% males; mean age 39±15 years [range, 20-76 years]) were included. All 19 patients underwent 2 detailed sinus rhythm electroanatomic endocardial voltage maps (average 385±177 points per map; range, 93-847 points). Time interval between the initial and repeat ablation procedures was mean 50±37 months (range, 9-162). No significant progression of voltage was observed (bipolar: 38 cm2 [interquartile range (IQR), 25-54] versus 53 cm2 [IQR, 25-65], P=0.09; unipolar: 116 cm2 [IQR, 61-209] versus 159 cm2 [IQR, 73-204], P=0.36) for the entire study group. There was a significant increase in RV volumes (percentage increase, 28%; 206 mL [IQR, 170-253] versus 263 mL [IQR, 204-294], P<0.001) for the entire study population. Larger scars at baseline but not changes over time were associated with a significant increase in RV volume (bipolar: Spearman ρ, 0.6965, P=0.006; unipolar: Spearman ρ, 0.5743, P=0.03). Most patients with progressive RV dilatation (8/14, 57%) had moderate (2 patients) or severe (6 patients) tricuspid regurgitation recorded at either initial or repeat ablation procedure. CONCLUSIONS: In patients with arrhythmogenic RV cardiomyopathy presenting with recurrent ventricular tachycardia, >10% increase in RV endocardial surface area of bipolar voltage consistent with scar is uncommon during the intermediate term. Most recurrent ventricular tachycardias are localized to regions of prior defined scar. Voltage indexed scar area at baseline but not changes in scar over time is associated with progressive increase in RV size and is consistent with adverse remodeling but not scar progression. Marked tricuspid regurgitation is frequently present in patients with arrhythmogenic RV cardiomyopathy who have progressive RV dilation.

3.
Heart ; 106(4): 280-286, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31439661

RESUMO

OBJECTIVES: To examine the prognostic significance of atrial fibrillation (AF) versus sinus rhythm (SR) on the management and outcomes of patients with severe aortic stenosis (AS). METHODS: 1847 consecutive patients with severe AS (aortic valve area ≤1.0 cm2 and aortic valve systolic mean Doppler gradient ≥40 mm Hg or peak velocity ≥4 m/s) and left ventricular ejection fraction ≥50% were identified. The independent association of AF and all-cause mortality was assessed. RESULTS: Age was 76±11 years and 46% were female; 293 (16%) patients had AF and 1554 (84%) had SR. In AF, 72% were symptomatic versus 71% in SR. Survival rate at 5 years for AF (41%) was lower than SR (65%) (age- and sex-adjusted HR=1.66 (1.40-1.98), p<0.0001). In multivariable analysis, factors associated with mortality included age (HR per 10 years=1.55 (1.42-1.69), p<0.0001), dyspnoea (HR=1.58 (1.33-1.87), p<0.0001), ≥ moderate mitral regurgitation (HR=1.63 (1.22-2.18), p=0.001), right ventricular systolic dysfunction (HR=1.88 (1.52-2.33), p<0.0001), left atrial volume index (HR per 10 mL/m2=1.13 (1.07-1.19), p<0.0001) and aortic valve replacement (AVR) (HR=0.44 (0.38-0.52), p<0.0001). AF was not a predictor of mortality independent of variables strongly correlated HR=1.02 (0.84-1.25), p=0.81). The 1-year probability of AVR following diagnosis of severe AS was lower in AF (49.8%) than SR (62.5%) (HR=0.73 (0.62-0.86), p<0.001); among patients with AF not referred for AVR, symptoms were frequently attributed to AF instead of AS. CONCLUSION: AF was associated with poor prognosis in patients with severe AS, but apparent differences in outcomes compared with SR were explained by factors other than AF including concomitant cardiac abnormalities and deferral of AVR due to attribution of cardiac symptoms to AF.

4.
J Clin Sleep Med ; 15(10): 1459-1468, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31596211

RESUMO

STUDY OBJECTIVES: A strong association between sleep-disordered breathing (SDB) and atrial fibrillation and/or atrial flutter (AF) has consistently been observed in epidemiologic and interventional studies. The effect of positive airway pressure (PAP) on AF recurrence is inconclusive. This study sought to evaluate the effectiveness of PAP therapy for SDB on AF recurrence. METHODS: This was a single-center, retrospective study conducted at a tertiary referral center. All adult patients who had SDB on polysomnography and underwent AF intervention (ablation or cardioversion) following polysomnography from January 1992-December 2014 were analyzed. Primary outcome was time to first-documented recurrence of AF after AF intervention by Kaplan-Meier estimates. RESULTS: Among 30,188 patients with obstructive and central SDB, 429 had this diagnosis before AF intervention; 269 were "PAP-adherent users," the remaining 160 were "PAP-nonusers." Patients in both groups had similar age, sex, body mass index (BMI), ejection fraction, left atrial volume index (LAVI), antiarrhythmic medications, diabetes mellitus, systemic hypertension, and heart failure diagnoses. Time to recurrence of AF postintervention was no different in PAP-adherent users and nonusers (4.8 and 4.1 months respectively, P = .7). Cardioversion (compared to catheter ablation) was the strongest independent predictor of recurrent AF (hazard ratio [HR] 2.02, 95% confidence interval [CI] 1.39-2.94, P < .001). BMI and LAVI were also significant predictors of recurrence in adjusted analyses (HR 1.01, 95% CI 1.003-1.023, P = .10 and HR 1.01, 95% CI 1.001-1.019, P = .024 respectively). CONCLUSIONS: Our study found no effect of PAP treatment of SDB on time to recurrence of AF post-AF intervention. Increased risk of recurrent AF was associated with high BMI and LAVI. These findings may affect the clinical management of AF.

6.
Histol Histopathol ; 34(11): 1255-1268, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30968943

RESUMO

BACKGROUND: Functional properties of the sinoatrial node (SAN) are known to differ between sexes. Women have higher resting and intrinsic heart rates. Sex determines the risk of developing certain arrhythmias such as sick sinus syndrome, which occur more often in women. We believe that a major contributor to these differences is in gender specific ion channel expression. METHODS: qPCR was used to compare ion channel gene expression in the SAN and right atrium (RA) between male and female rats. Histology, immunohistochemistry and signal intensity analysis were used to locate the SAN and determine abundance of ion channels. The effect of nifedipine on extracellular potential recording was used to determine differences in beating rate between sexes. RESULTS: mRNAs for Cav1.3, Kir3.1, and Nkx2-5, as well as expression of the L-Type Ca²âº channel protein, were higher in the female SAN. Females had significantly higher intrinsic heart rates and the effect of nifedipine on isolated SAN preparations was significantly greater in male SAN. Computer modelling using a SAN cell model demonstrated a higher propensity of pacemaker-related arrhythmias in females. CONCLUSION: This study has identified key differences in the expression of Cav1.3, Kir3.1 and Nkx2-5 at mRNA and/or protein levels between male and female SAN. Cav1.3 plays an important role in the pacemaker function of the SAN, therefore the higher intrinsic heart rate of the female SAN could be caused by the higher expression of Cav1.3. The differences identified in this study advance our understanding of sex differences in cardiac electrophysiology and arrhythmias.

7.
Am J Cardiol ; 123(4): 632-637, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30554649

RESUMO

Periodic limb movements in sleep (PLMS) are associated with adverse outcomes in patients with heart failure (HF). The aim of this study was to investigate whether PLMS change in response to adaptive servo-ventilation (ASV) for central sleep apnea (CSA) in patients with HF. We examined polysomnographic studies conducted between 2010 and 2014 at Mayo Clinic, Rochester, Minnesota (n = 14,444). In those, 314 of 579 patients with CSA completed the sleep study with a protocol that began with diagnostic polysomnography, followed by continuous positive airway pressure, and, for persistent CSA, by ASV titration. Patients with HF (n = 118) had a significantly higher median PLM index compared with those without HF (n = 196): 33.7 versus 6.1 events/h (p <0.001). HF was associated with a significant PLM arousal index (PLMAI) increase from diagnostic trial to ASV (odds ratio [OR]  = 1.79, p = 0.032) after adjusting for demographics, co-morbidities and medications. In patients aged >68 years, HF was associated with PLMI and PLMAI increases during ASV (OR  = 2.16, p = 0.016 and OR  = 2.05, p = 0.024), which persisted in multivariable models (OR  = 2.36, p = 0.025 and OR  = 2.33, p = 0.026). In multivariable analysis, patients with ejection fraction ≤45% had higher odds of increased PLMAI during ASV than those with ejection fraction >45% (OR  = 1.98, p = 0.022). In conclusion, PLMS may increase in HF patients after suppression of CSA by ASV. Whereas the clinical significance of increased post-ASV PLMS in HF prognosis needs to be determined, these increases may contribute to worsening outcomes in HF patients with CSA treated with ASV.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas , Insuficiência Cardíaca/complicações , Síndrome da Mioclonia Noturna/epidemiologia , Apneia do Sono Tipo Central/terapia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome da Mioclonia Noturna/diagnóstico , Polissonografia , Prevalência , Estudos Retrospectivos , Apneia do Sono Tipo Central/complicações , Apneia do Sono Tipo Central/diagnóstico
8.
Epilepsia ; 59(10): 1973-1981, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30246243

RESUMO

OBJECTIVE: We aimed to determine the frequency of probable obstructive sleep apnea (pOSA) in refractory epilepsy monitoring unit inpatients and clinical features associated with pOSA, including risk for sudden unexpected death in epilepsy (SUDEP). METHODS: We prospectively recruited 49 consecutive adult patients admitted to the Mayo Clinic Epilepsy Monitoring Unit with focal, generalized, or unclassified epilepsy syndromes. pOSA was identified using oximetric oxyhemoglobin desaturation index (ODI) and the Sleep Apnea-Sleep Disorders Questionnaire (SA-SDQ) and STOP-BAG screening tools. Revised SUDEP Risk Inventory (rSUDEP-7) scores were calculated, and epilepsy patients with and without pOSA were compared with Wilcoxon signed-rank tests. Correlation and regression analyses were utilized to determine relationships between pOSA and rSUDEP-7 scores. RESULTS: Thirty-five percent of patients had pOSA, with a mean ODI of 11.3 ± 5.1/h (range = 5.1-22.8). Patients with pOSA were older and heavier, and more frequently had a focal epilepsy syndrome and longer epilepsy duration, with higher SA-SDQ and STOP-BAG scores (all P < 0.05). Median rSUDEP-7 score was 3 ± 1.4 (range = 0-6). Higher rSUDEP-7 scores were positively correlated with higher ODI (P = 0.036). rSUDEP-7 score ≥ 5 was associated with pOSA by ODI, SA-SDQ, and STOP-BAG questionnaire criteria (P < 0.05). SIGNIFICANCE: Our pilot study identified a high frequency of pOSA in refractory epilepsy monitoring patients, finding that pOSA patients were older and heavier, with higher screening symptoms for sleep apnea and more frequent focal seizures with a longer epilepsy duration. We also found a possible association between OSA and SUDEP risk. Identification and treatment of OSA in patients with epilepsy could conceivably provide a novel approach toward preventing the risk of SUDEP. Future studies with polysomnography are needed to confirm predictive features for OSA in epilepsy populations, and to determine whether OSA is associated with SUDEP risk.


Assuntos
Morte Súbita/epidemiologia , Epilepsia , Apneia Obstrutiva do Sono/complicações , Adulto , Epilepsia/complicações , Epilepsia/epidemiologia , Epilepsia/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Inquéritos e Questionários , Adulto Jovem
9.
Pacing Clin Electrophysiol ; 40(11): 1260-1268, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28846153

RESUMO

BACKGROUND: Cardiovascular implantable electronic devices (CIEDs) can be life-saving. However, complications from CIED infection can be life-threatening, often requiring device removal. Despite publication of CIED infection management guidelines, there remains marked variation in clinical practice. OBJECTIVE: To better understand and quantify these differences, we conducted a multinational survey of practitioners of CIED management. METHODS: An electronic survey was sent to Heart Rhythm Society members, spanning 70 countries across six continents. All responses were collected anonymously. RESULTS: 227 out of 3,600 (6.3%) responded to the survey. The majority of surveys were completed by practitioners from the United States (168; 68.3%) and 53.8% of these practiced in academic medical centers. The large majority (92.7%) of sites had protocols to ensure appropriate timing of prophylactic antibiotics. Superficial (incisional) site infections were treated with antibiotics alone 52.5% of the time (consistent with guidelines); in contrast, deep pocket infections were treated with antibiotics (with device removal) in accordance to guidelines only 37.4% of the time. Almost all providers (98.7%) were inclined to perform complete hardware removal in cases of CIED-related endocarditis. In contrast, 82.2% of survey participants suggested complete CIED system removal in patients with an occult Gram-positive bacteremia, 65.5% with occult Gram-negative bacteremia, and 59.3% with prolonged bacteremia due to a source other than CIED. CONCLUSIONS: These data suggest wide variability in clinical practice in managing CIED infection with significant deviations from published guidelines. There is critical need to increase awareness and develop institutional protocols to ensure adherence with evidence-based guidelines to optimize outcomes.


Assuntos
Cardiologistas , Desfibriladores Implantáveis , Conhecimentos, Atitudes e Prática em Saúde , Marca-Passo Artificial , Padrões de Prática Médica/estatística & dados numéricos , Infecção da Ferida Cirúrgica/prevenção & controle , Humanos , Inquéritos e Questionários
11.
Open Heart ; 4(1): e000561, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28409011

RESUMO

OBJECTIVE: Sudden cardiac arrest (SCA) is the most devastating outcome in hypertrophic cardiomyopathy (HCM). We evaluated repolarisation features on the surface electrocardiogram (ECG) to identify the potential risk factors for SCA. METHODS: Data was collected from 52 patients with HCM who underwent implantable cardioverter defibrillator (ICD) implantation. Leads V2 and V5 from the ECG closest to the time of ICD implant were utilised for measuring the Tpeak-Tend interval (Tpe), QTc, Tpe/QTc, T-wave duration and T-wave amplitude. The presence of the five traditional SCA-associated risk factors was assessed, as well as the HCM risk-SCD score. RESULTS: 16 (30%) patients experienced aborted cardiac arrest over 8.5±4.1 years, with 9 receiving an ICD shock and 7 receiving ATP. On univariate analysis, T-wave amplitude was associated with appropriate ICD therapy (HR per 0.1 mV 0.79, 95% CI 0.56 to 0.96, p=0.02). Aborted SCA was not associated with a greater mean QTc duration, Tpeak-Tend interval, T-wave duration, or Tpe/QT ratio. Multivariate analysis (adjusting for cardinal HCM SCA-risk factors) showed T-wave amplitude in Lead V2 was an independent predictor of risk (adjusted HR per 0.1 mV 0.74, 95% CI 0.57 to 0.97, p=0.03). Addition of T-wave amplitude in Lead V2 to the traditional risk factors resulted in significant improvement in risk stratification (C-statistic from 0.65 to 0.75) but did not improve the performance of the HCM SCD-risk score. CONCLUSIONS: T-wave amplitude is a novel marker of SCA in this high risk HCM population and may provide incremental predictive value to established risk factors. Further work is needed to define the role of repolarisation abnormalities in predicting SCA in HCM.

13.
Indian Pacing Electrophysiol J ; 16(1): 19-30, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27485561

RESUMO

Although great strides have been made in the areas of ventricular pacing, it is still appreciated that dyssynchrony can be malignant, and that appropriately placed pacing leads may ameliorate mechanical dyssynchrony. However, the unknowns at present include: 1. The mechanisms by which ventricular pacing itself can induce dyssynchrony; 2. Whether or not various pacing locations can decrease the deleterious effects caused by ventricular pacing; 3. The impact of novel methods of pacing, such as atrioventricular septal, lead-less, and far-field surface stimulation; 4. The utility of ECG and echocardiography in predicting response to therapy and/or development of dyssynchrony in the setting of cardiac resynchronization therapy (CRT) lead placement; 5. The impact of ventricular pacing-induced dyssynchrony on valvular function, and how lead position correlates to potential improvement. This review examines the existing literature to put these issues into context, to provide a basis for understanding how electrical, mechanical, and functional aspects of the heart can be distorted with ventricular pacing. We highlight the central role of the mitral valve and its function as it relates to pacing strategies, especially in the setting of CRT. We also provide future directions for improved pacing modalities via alternative pacing sites and speculate over mechanisms on how lead position may affect the critical function of the mitral valve and thus overall efficacy of CRT.

14.
J Cardiovasc Electrophysiol ; 26(2): 158-63, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25425429

RESUMO

INTRODUCTION: Catheter ablation of ventricular arrhythmia (VA) at the fibrous aortic mitral continuity (AMC) has been described, yet the nature of the arrhythmogenic substrate remains unknown. METHODS: Procedural records of 528 consecutive patients undergoing ablation of VA at Mayo Clinic, Rochester, MN, were reviewed. The electrocardiographic and electrophysiologic characteristics of patients with successful ablation at the AMC were analyzed to characterize the underlying arrhythmogenic substrate. RESULTS: Of the 21 patients (mean age 53.2 ± 13.4 years, 47.6% male) who underwent ablation of VA at the AMC with acute success, prepotentials (PPs) were found at the ablation sites preceding the ventricular electrogram (VEGM) during arrhythmias in 13 (61.9%) patients and during sinus rhythm in 7 (53.8%) patients. VAs with PPs were associated with a significantly higher burden of premature ventricular complexes (PVCs; 26.1 ± 10.9% vs. 14.9 ± 10.1%, P = 0.03), shorter VEGM to QRS intervals (9.0 ± 28.5 milliseconds vs. 33.1 ± 8.8 milliseconds, P = 0.03), lower pace map scores (8.7 ± 1.6 vs. 11.4 ± 0.8, P = 0.001), and a trend toward shorter V-H intervals during VA (32.1 ± 38.6 milliseconds vs. 76.3 ± 11.1 milliseconds, P = 0.06) as compared to those without PP. A strong and positive correlation was found between V-H interval and QRS duration during arrhythmia in those with PPs (B = 2.11, R(2) = 0.97, t = 13.7, P < 0.001) but not in those without PPs. CONCLUSION: Local EGM characteristics and relative activation time of the His bundle suggest the possibility of conduction tissue as the origin for VA arising from the fibrous AMC. Specific identification and targeting of PPs when ablating VAs at this location may improve procedural success.


Assuntos
Valva Aórtica/fisiopatologia , Técnicas Eletrofisiológicas Cardíacas , Sistema de Condução Cardíaco/fisiopatologia , Ventrículos do Coração/fisiopatologia , Valva Mitral/fisiopatologia , Taquicardia Ventricular/diagnóstico , Complexos Ventriculares Prematuros/diagnóstico , Potenciais de Ação , Adulto , Idoso , Valva Aórtica/cirurgia , Fascículo Atrioventricular/fisiopatologia , Ablação por Cateter , Eletrocardiografia , Feminino , Sistema de Condução Cardíaco/cirurgia , Ventrículos do Coração/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Minnesota , Valva Mitral/cirurgia , Valor Preditivo dos Testes , Estudos Retrospectivos , Taquicardia Ventricular/etiologia , Taquicardia Ventricular/fisiopatologia , Taquicardia Ventricular/cirurgia , Fatores de Tempo , Resultado do Tratamento , Complexos Ventriculares Prematuros/etiologia , Complexos Ventriculares Prematuros/fisiopatologia , Complexos Ventriculares Prematuros/cirurgia
15.
World J Cardiol ; 6(11): 1223-6, 2014 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-25429334

RESUMO

We report an unusual case of an isolated right ventricular infarction with haemodynamic compromise caused by spontaneous isolated proximal occlusion of the right ventricular branch of the right coronary artery (RCA), successfully treated by balloon angioplasty. A 58-year-old gentleman presented with epigastric pain radiating into both arms. Electrocardiograph with right ventricular leads confirmed ST elevation in V4R and a diagnosis of isolated right ventricular infarction was made. Urgent primary percutaneous intervention was performed which revealed occlusion of the right ventricular branch of the RCA. During the procedure, the patient's blood pressure dropped to 80/40 mmHg, and echocardiography showed impaired right ventricular systolic function. Despite aggressive fluid resuscitation, the patient remained hypotensive, continued to have chest pain and persistent electrocardiograph changes, and hence balloon angioplasty was performed on the proximal right ventricular branch which restored flow to the vessel and revealed a severe ostial stenosis. This was treated with further balloon angioplasty which restored TIMI 3 flow with resolution of patient's symptoms. Repeat echocardiography showed complete resolution of the ST-elevation in leads V4R and V5R and partial resolution in V1. Subsequent dobutamine-stress echocardiography at 4 wk showed good left and right ventricular contractions. The patient was discharged after a 3-d in-patient stay without any complications.

16.
BMJ Case Rep ; 20112011 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-22669884

RESUMO

A 78-year-old Caucasian male presented with a 5-day progressive history of fever, vomiting and dyspnoea. Initial clinical examination revealed fever, sinus tachycardia, hypotension, peripheral cyanosis and a systolic murmur. Investigations revealed a multiple organ dysfunction syndrome. A repeat trans-thoracic echocardiogram showed a basal inferoseptum aneurysm associated with an acquired ventricular septal defect not demonstrated on initial scan. An intra-aortic balloon pump was urgently inserted and he underwent surgical repair of the defect, 7 days after his initial presentation. He unfortunately died from postoperative complications.


Assuntos
Comunicação Interventricular/diagnóstico , Isquemia Miocárdica/diagnóstico , Doença Aguda , Idoso , Febre/etiologia , Comunicação Interventricular/complicações , Humanos , Masculino , Isquemia Miocárdica/complicações
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