Author + information
- Riccardo Cappato, MD⁎ (, )
- Hugh Calkins, MD,
- Shih-Ann Chen, MD,
- Wyn Davies, MD,
- Yoshito Iesaka, MD,
- Jonathan Kalman, MD,
- You-Ho Kim, MD,
- George Klein, MD,
- Andrea Natale, MD,
- Douglas Packer, MD,
- Cristian Ricci, PhD,
- Allan Skanes, MD and
- Marco Ranucci, MD, PhD
- ↵⁎Arrhythmia and Electrophysiology Center, University of Milan, IRCCS Policlinico San Donato, Via Morandi 30, 20097 San Donato Milanese, Milan, Italy
To the Editor: Catheter ablation is increasingly being offered for the curative treatment of atrial fibrillation (AF). Generally, the procedure is safe and effective (1), but the intense intraprocedural and post-procedural anticoagulation regimen used, together with extensive catheter manipulation and application of radiofrequency energy, may expose patients to an excessive risk for bleeding. Although intraprocedural tamponade has been reported (1,2), little is known about the incidence of delayed cardiac tamponade (DCT). We investigated the incidence, modes of presentation, and outcomes of DCT in a large population of patients undergoing this procedure.
An anonymous volunteer reporting method was used to identify cases that occurred between January 1995 and December 2006 at 102 centers contributing to our worldwide surveys on the efficacy and safety of AF ablation (1,2). We defined DCT as hypotension or cardiogenic shock requiring pericardial drainage or causing death due to documented pericardial effusion occurring at least 1 h post-procedurally but attributable to the ablation procedure. Center experience, mapping and ablation technique and catheter used, type of AF treated, intraprocedural and post-procedural anticoagulation strategy, and the occurrence of tamponade during the procedure were compared at centers with and without cases of DCT to determine potential risk factors. This survey was approved by the institutional review board at Policlinico San Donato.
Patient and center characteristics were described by location indexes if continuous or by frequencies and percentages if noncontinuous. Contingency tables were created to calculate the influence on the occurrence of DCT of center characteristics with regard to experience, mapping and ablation strategy and catheter used, type of AF, and anticoagulation strategy during and after the procedure. Differences were calculated using chi-square tests of independence. If any of the expected cell counts were lower than 5, the Fisher's exact test was applied using the algorithm proposed by Mehta and Patel where the contingency table dimensions were greater than 2 × 2. All the center-related variables that were associated (p < 0.10) with the presence of at least 1 DCT event were subsequently tested in a multivariate model. Only the variable with the highest statistical significance was tested in the multivariate model.
Forty-five cases of DCT after 27,921 procedures performed in 21,478 patients were reported. Patients presented with DCT a median of 12 days (range: 0.2 to 45 days) after the ablation procedures. Four patients presented during their initial hospital stays, whereas 41 patients were discharged after their ablation procedures and presented subsequently to their primary care physicians, emergency departments, or cardiologists with warning symptoms. Echocardiography proved diagnostic in all such cases.
Most patients presented with nonspecific symptoms, including constant thoracic pain, neck or back pain, pain during breathing, dyspnea, dizziness, nausea, fever, peripheral or global edema, impending sense of doom or death, nausea, fever or general malaise. One patient had cardiac arrest while swimming and was found to have cardiac tamponade after resuscitation. Another patient died suddenly and was found to have a large pericardial effusion during the in-hospital resuscitation attempt. In 6 patients, hypotension developed without warning. Two patients (5%) died, 1 from cardiac arrest 14 days after the procedure and 1 at 30 days after a procedure complicated by cerebral thromboembolism that had occurred 24 h after ablation. The mode of presentation of hypotension varied, with 39 patients exhibiting gradual progression to cardiac tamponade and 6 patients experiencing severe symptoms within minutes.
Therapy included pericardiocentesis in 36 patients and also required pleural evacuation in another patient. A pericardial surgical window was needed in 1 patient and open-chest surgery in 7 patients. In 36 patients, the hemorrhagic content of the pericardial fluid was reported at visual inspection, whereas serous effusion was the only finding in the remaining 9 patients.
When tested in the multivariate model (Table 1), the following factors were independent predictors of at least 1 DCT event: large volume of patients treated (odds ratio: 5.03), use of irrigation catheter (odds ratio: 2.77), and treatment of paroxysmal AF only (odds ratio: 3.97).
DCT occurred in 0.2% of patients in our series. Although warning symptoms were present in most patients, hypotension and shock were the presentation in 13% of patients. Warning symptoms were variable, including thoracic, neck and back pain, and dyspnea and sometimes nonspecific symptoms such as dizziness, nausea, fever, peripheral or global edema, impending sense of doom or death, or general malaise. Eighty-four percent of patients sought care from their primary care physicians, emergency departments, or general cardiologists rather than from the interventional electrophysiologist. Evolution to cardiac tamponade mostly occurred over hours or days, allowing access to medical aid, but hemodynamic deterioration within minutes from the onset of symptoms was observed in 13% of patients.
Retrospective series based on anonymous identification of cases and retrospective medical record review have limitations. Although anonymous identification of cases facilitates reporting of data on poor outcomes, variability in prospective monitoring by many physicians and of many procedures prevents accurate assessment of the incidence of events, their presentation, and outcomes. These limitations are further expanded by the late occurrence of DCT in relationship to the date of AF ablation.
Dr. Cappato is a consultant for Biosense Webster, St. Jude Medical, BARD, Medtronic, ELA Sorin, Abbott Pharma, Boehringer Ingelheim, Pfizer, and Bayer Health; has equity and intellectual property rights in Cameron Health; is on the Speaker's Bureau of Boston Scientific, Medtronic, St. Jude Medical, Biosense Webster, BARD, Sanofi Aventis, Abbott Pharma, Boehringer Ingelheim, Pfizer, and Bayer Health; is an investigator for Medtronic, Biosense Webster, Sanofi Aventis, Cameron Health, and BARD; and has received grants from Boston Scientific, Medtronic, St. Jude Medical, Biosense Webster, BARD, and ELA Sorin. Dr. Calkins is a consultant for Ablation Frontiers, Biosense Webster, Medtronic, ProRhythm, and Sanofi Aventis. Dr. Chen has received research grants from St. Jude Medical and Boston Scientific. Dr. Davies is on the advisory board of CryoCath. Dr. Kalman has received research grants and fellowship support from St. Jude Medical, Biosense Webster, and Medtronic. Dr. Klein is a consultant for Medtronic; is a speaker for St. Jude Medical and Boston Scientific; and is on the board of trustees for CrycoCath Technologies. Dr. Natale is a speaker for and on the advisory board of St. Jude Medical and Biosense Webster; is a speaker for Medtronic and LifeWatch; is on the advisory board of Stereotaxis; and has received research grants from St. Jude Medical. Dr. Packer has provided consulting services for Biosense Webster, Boston Scientific, Cardialysis, Cardiomedics, Endosense, CyberHeart, Medtronic, CryoCath, Sanofi-Aventis, Siemens, St. Jude Medical, GE Healthcare, Philips Healthcare, CardioFocus, InnerPulse Coherex, OrthoMcNeill, MediComp, Siemens AG, Skyline Ventures, Toray Industries, and Imricor; has received research funding from the NIH, Medtronic, CryoCath LP, Taermedical (EP Limited), Endosense, EpiEP, EP Advocate, Population Health Research Institute-Hamilton Health Sciences General Hospital, St. Jude Medical, Siemens AcuNav, Minnesota Partnership for Biotechnology and Medical Genomics/University of Minnesota, Biosense Webster, and Boston Scientific; and has received royalties from Blackwell Publishing and St. Jude Medical. Dr. Skanes is on the physician advisory board for Biosense Webster and General Electric; and is a speaker and research grant for Biosense Webster.
- American College of Cardiology Foundation
- Cappato R.,
- Calkins H.,
- Chen S.A.,
- et al.
- Cappato R.,
- Calkins H.,
- Chen S.A.,
- et al.