Catheter Ablation for Atrial Fibrillation

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A No Chemotherapy Probability of Remaining Untreated

P=0.006

No SF3B1 mutation (N=54) SF3B1 mutation (N=7)

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B Chemotherapy Probability of Remaining Untreated

1.0 P=0.21

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(Fig. 1A), but the time to first treatment is a “soft” end point. In the patients who received chemotherapy, the SF3B1 mutation was associated with a somewhat earlier initiation of treatment (median, 15 months) than in patients without the SF3B1 mutation (median, 24 months), but the difference was not significant (P = 0.21) (Fig. 1B). More definitive findings will require analysis of serial samples obtained from a larger number of patients so that the relation between the SF3B1 mutation and natural history can be evaluated more precisely. Lili Wang, M.D., Ph.D. Donna Neuberg, Sc.D. Catherine J. Wu, M.D.

No SF3B1 mutation (N=23)

SF3B1 mutation (N=7)

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Figure 1. Mutation in SF3B1 and Earlier Initiation of Treatment in Patients with Chronic Lymphocytic Leukemia. Kaplan–Meier estimates of the probability of the time after diagnosis to first therapy according to the presence or absence of the SF3B1 mutation in patients who had not received chemotherapy (Panel A) and patients who had received chemotherapy (Panel B) are shown. Significance was calculated with the use of the log-rank test.

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Dana–Farber Cancer Institute Boston, MA [email protected] Since publication of their article, the authors report no further potential conflict of interest.

Catheter Ablation for Atrial Fibrillation To the Editor: Wazni et al. (Dec. 15 issue)1 provide a comprehensive review on catheter ablation for atrial fibrillation. However, by presenting the potential complications of atrial fibrillation ablation as reported in international surveys,2 the authors overlooked two important issues. First, they stated that “cerebrovascular thromboembolism has been reported to occur in up to 2% of patients.” This is true only for symptomatic strokes, but silent ischemic strokes may develop in up to 14% of patients undergoing atrial fibrillation ablation as a result of the procedure.3 Second, the authors did not mention a probably irreversible complication of atrial fibrillation ablation: the “stiff left atrial syndrome.” Gibson et al. described this syndrome in 1.4% of patients undergoing atrial fibrillation ablation, but the

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true incidence is probably higher, since they included only symptomatic patients with a stiff left atrium.4 The prognostic consequences of these complications are currently unknown, but they underline the urgent need for data on the real impact of atrial fibrillation ablation on major clinical outcomes; the principle of “primum non nocere” for atrial fibrillation ablation is yet to be proved.5 Andrei D. Margulescu, M.D. Carol Davila University of Medicine and Pharmacy Bucharest, Romania [email protected] No potential conflict of interest relevant to this letter was reported. 1. Wazni O, Wilkoff B, Saliba W. Catheter ablation for atrial

fibrillation. N Engl J Med 2011;365:2296-304.

n engl j med 366;11 nejm.org march 15, 2012

The New England Journal of Medicine Downloaded from nejm.org on March 15, 2012. For personal use only. No other uses without permission. Copyright © 2012 Massachusetts Medical Society. All rights reserved.

correspondence 2. Cappato R, Calkins H, Chen SA, et al. Updated worldwide

survey on the methods, efficacy, and safety of catheter ablation for human atrial fibrillation. Circ Arrhythm Electrophysiol 2010; 3:32-8. 3. Gaita F, Caponi D, Pianelli M, et al. Radiofrequency catheter ablation of atrial fibrillation: a cause of silent thromboembolism? Magnetic resonance imaging assessment of cerebral thromboembolism in patients undergoing ablation of atrial fibrillation. Circulation 2010;122:1667-73. 4. Gibson DN, Di Biase L, Mohanty P, et al. Stiff left atrial syndrome after catheter ablation for atrial fibrillation: clinical characterization, prevalence, and predictors. Heart Rhythm 2011; 8:1364-71. [Erratum, Heart Rhythm 2011;8:1828.] 5. Fraser AG, Daubert JC, Van de Werf F, et al. Clinical evaluation of cardiovascular devices: principles, problems, and proposals for European regulatory reform: report of a policy conference of the European Society of Cardiology. Eur Heart J 2011;32: 1673-86.

No potential conflict of interest relevant to this letter was reported. 1. Barrett CD, Di Biase L, Natale A. How to identify and treat

patient with pulmonary vein stenosis post atrial fibrillation ablation. Curr Opin Cardiol 2009;24:42-9. 2. Aguilar-Cabello M, Martín-Bermúdez R, Jiménez-Jiménez J, Egea-Guerrero JJ, García-Lombardo AM. Threatening hemoptysis and pulmonary vein stenosis after ablation due to atrial fibrillation. Med Intensiva 2012;36:56-7. 3. Nehra D, Liberman M, Vagefi PA, et al. Complete pulmonary venous occlusion after radiofrequency ablation for atrial fibrillation. Ann Thorac Surg 2009;87:292-5.

To the Editor: We would like to share some thoughts regarding the development of pulmonary hypertension in patients with iatrogenic pulmonary-vein stenosis.1,2 Pulmonary hypertension appears to be a very rare complication after pulmonary-vein ablation, but it may be under diagnosed. We have previously described cardiopulmonary hemodynamic clues (i.e., variations in the pulmonary-artery wedge pressures between lung zones2,3 and the regional loss of V waves on pulmonary-artery wedge pressure tracings for the diagnosis of pulmonary-vein stenosis). There are unanswered questions regarding the development of pulmonary hypertension: Is it related to the number of stenosed vessels or to the progression from stenosis to complete occlusion? Is it related to the technique used? Also, when and how should patients — particularly those who are asymptomatic — be screened for clinically significant pulmonary hypertension complicating pulmonary-vein stenosis? Furthermore, does the presence of pulmonary hypertension predict the failure or success of stenting for pulmonary-vein stenosis? We believe that further clinical studies need to focus on identifying the frequency of and risk factors associated with pulmonary hypertension and diagnostic clues for the early detection of this condition in patients with pulmonary-vein stenosis after ablation.

To the Editor: Wazni et al. state that pulmonary-vein stenosis is a complication of radiofrequency ablation for atrial fibrillation. However, the authors make no mention of a potentially fatal presentation, hemoptysis. The rapid expansion of the use of ablation procedures is leading to a higher incidence of pulmonary-vein stenosis in adults. Pulmonaryvein stenosis was previously a very rare entity that was mainly a primary condition and occurred in children.1 The presentation with nonspecific symptoms contributes to delays in diagnosis. Although its long-term efficacy is not well known, the proposed treatment is angioplasty and stenting,1 followed by anticoagulation. The treatment of patients with active hemoptysis is more complicated. We have reported the case of a patient with life-threatening hemoptysis that required urgent lobectomy.2 A previous similar article mentioned the need for lung resection after pulmonary-vein stenosis in a patient secondary to radiofrequency ablation.3 Both patients had successful outcomes. Pulmonary-vein stenosis after ablation is a relatively new iatrogenic entity, and the delay in its diagnosis can complicate its treatment. When a new form of technology emerges, we must Mateo Porres-Aguilar, M.D. know the potential complications so that we Texas Tech University Health Sciences Center may develop appropriate and timely treatment El Paso, TX options. Saurav Chatterjee, M.D. Juan J. Egea-Guerrero, M.D., Ph.D. Maimonides Medical Center Brooklyn, NY Rafael Martín-Bermudez, M.D., Ph.D. [email protected] Jaume Revuelto-Rey, M.D. Debabrata Mukherjee, M.D. Virgen del Rocio University Hospital Seville, Spain [email protected]

Texas Tech University Health Sciences Center El Paso, TX



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No potential conflict of interest relevant to this letter was reported. 1. Yang HM, Lai CK, Patel J, et al. Irreversible intrapulmonary

vascular changes after pulmonary vein stenosis complicating catheter ablation for atrial fibrillation. Cardiovasc Pathol 2007; 16:51-5. 2. Porres-Aguilar M, Fernandez G, Elliott CG. Cardiopulmonary hemodynamic clues for pulmonary vein stenosis diagnosis. Pulm Circ 2011;1:504-5. 3. Robbins IM, Colvin EV, Doyle TP, et al. Pulmonary vein stenosis after catheter ablation for atrial fibrillation. Circulation 1998;98:1769-75.

To the Editor: We think Wazni and colleagues should have been more cautious in their discussion of the potential role of catheter ablation in patients with persistent atrial fibrillation and heart failure. We performed a randomized trial comparing medical therapy with catheter ablation in 41 patients with persistent atrial fibrillation, symptomatic heart failure (New York Heart Association functional class III heart failure in 37 patients), and left ventricular systolic dysfunction (mean left ventricular ejection fraction, 17.7%).1 Only 50% of the patients remained in sinus rhythm 9 months after ablation. The left ventricular ejection fraction, quality of life, and level of N-terminal B-type natriuretic peptide did not improve more after ablation than after medical therapy. The value of ablation was further questionable because of the complication rate: in 27 procedures, there was one stroke (representing 4% of patients), there were two episodes of cardiac tamponade (8%), and there was one hospitalization for heart failure (4%). Our findings are in striking contrast to those reported in other patient populations. Michael R. MacDonald, M.D. Golden Jubilee National Hospital Glasgow, United Kingdom [email protected]

John J.V. McMurray, M.D. British Heart Foundation Glasgow Cardiovascular Research Centre Glasgow, United Kingdom

Mark C. Petrie, M.D. Golden Jubilee National Hospital Glasgow, United Kingdom No potential conflict of interest relevant to this letter was reported. 1. MacDonald MR, Connelly DT, Hawkins NM, et al. Radiofre-

quency ablation for persistent atrial fibrillation in patients with advanced heart failure and severe left ventricular systolic dysfunction: a randomised controlled trial. Heart 2011;97:740-7.

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The Authors Reply: In reply to Margulescu: silent thromboembolism remains a concern during any ablation in the systemic side of the heart. However, in the study described by Gaita et al. (cited in Margulescu’s letter), several factors may have contributed to the high incidence. These factors include discontinuing oral anticoagulation before the ablation, giving heparin after the transseptal puncture, and then keeping the activated clotting time between 250 and 300 seconds rather than higher than 350 seconds. These factors were very well addressed in the editorial by Michaud1 that accompanied the article by Gaita et al. This issue requires further study with standardized periprocedural anticoagulation strategies. Also, the risk may be higher with nonir rigated ablation systems. The stiff left atrial syndrome may develop after ablation in rare cases. One study has highlighted this occurrence.2 However, it was also noted that severe left atrial scarring and high left atrial pressure in addition to diabetes and sleep apnea predicted the development of this syndrome. It is possible that this was the natural history of the syndrome that was exacerbated with ablation in these patients. We agree with Egea-Guerrero and colleagues regarding their comments on pulmonary-vein stenosis. Fortunately, when ablation is limited to the antrum and atrial side of the pulmonary veins, stenosis is rare. Nevertheless, when it is severe and involves more than one pulmonary vein, stenosis may cause a variety of symptoms, including some with life-threatening complications. The treatment should always be to try to recanalize the pulmonary veins before any drastic measures if possible. The many different presentations of the pulmonary-vein stenosis syndrome were described when atrial fibrillation ablation was first used. We also agree with Porres-Aguilar and colleagues that pulmonary hypertension from severe pulmonary-vein stenosis is very rare and that in select situations more extensive evaluation and testing are needed. With regard to the comments by MacDonald and colleagues: in the article, we do mention that ablation for persistent or permanent atrial fibrillation is still considered an off-label use. We also said that ablation is less effective in patients with persistent atrial fibrillation and heart failure. However, high success rates and



correspondence

low complication rates as described are achiev- Oussama Wazni, M.D. able in high-volume, experienced centers. A re- Walid Saliba, M.D. cent meta-analysis by Dagres et al.3 showed Cleveland Clinic OH that atrial fibrillation ablation in patients with Cleveland, [email protected] systolic left ventricular dysfunction results in Since publication of their article, the authors report no furclinically significant improvement of left ven- ther potential conflict of interest. tricular function. Also, the Pulmonary Vein 1. Michaud GF. Silent cerebral embolism during catheter ablaAntrum Isolation versus AV Node Ablation with tion of atrial fibrillation: how concerned should we be? Circulation 2010;122:1662-3. Bi-Ventricular Pacing for Treatment of Atrial 2. Saad EB, Marrouche NF, Saad CP, et al. Pulmonary vein steFibrillation in Patients with Congestive Heart nosis after catheter ablation of atrial fibrillation: emergence of Failure (PABA-CHF) study (ClinicalTrials.gov a new clinical syndrome. Ann Intern Med 2003;138:634-8. 3. Dagres N, Varounis C, Gaspar T, et al. Catheter ablation for number, NCT00599976) showed that atrial fi- atrial fibrillation in patients with left ventricular systolic dysbrillation ablation was superior to the best function: a systematic review and meta-analysis. J Card Fail strategy for rate control with atrioventricular- 2011;17:964-70. 4. Khan MN, Jaïs P, Cummings J, et al. Pulmonary-vein isolanode ablation and pacing in patients with atrial tion for atrial fibrillation in patients with heart failure. N Engl J 4 fibrillation and heart failure. Med 2008;359:1778-85.

The Road Less Traveled To the Editor: There is great irony in the fact that Fingold’s Perspective article (Dec. 29 issue)1 appeared a few pages after an article about accountable care. At the medical home where I practice, the social worker and I are integrated on the same team. She handles phone calls with Medicaid, allowing me to spend my time doctoring. I talk to the pharmacist in the room with the patient. And when our patient arrives at the emergency department, the nurse care manager has called ahead, communicating the care plan. We cannot be accountable without teams. It makes no sense for the primary care physician and the patient, all by themselves, to succeed against all odds through extraordinary sagas of self-sacrifice. Working harder will not fix broken systems. Being a member of a team does not lessen the “deep satisfaction with the road I’ve chosen to travel” — it magnifies it. To the deep satisfaction of doing the team’s best for the patient is added the deep satisfaction of being part of a great team and the deep satisfaction of going home and spending time with loved ones, instead of worrying about what might have fallen through the cracks. Stuart M. Pollack, M.D. Brigham and Women’s Hospital Boston, MA [email protected]

No potential conflict of interest relevant to this letter was reported. 1. Fingold DR. The road less traveled. N Engl J Med 2011;365:

2449-51.

To the Editor: Fingold’s article does little to address medical students’ concerns about a career in primary care and reinforces the misconception that family physicians are little more than medical social workers and “referralists.” The “primary” in primary care was meant to describe the physician who is the primary source of medical care for the patient and family. It has degenerated into the idea that primary care is first-contact, low-level, noninterventional care, the purpose of which is to guide the patient to the “provider” who can actually offer care. The lumping of several specialties together into the primary care category and the assumption that each includes the same or similar scope have resulted in a degradation of the value and scope of family medicine and have caused family physicians who do wish to provide full-scope care to spend inordinate resources fighting with colleagues who wish to limit the types of care provided. Family physicians can be the foundation of the rebuilding of the American health care system, if their colleagues will allow it.



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