J Thorac Cardiovasc Surg 2003;126:1190-1192
© 2003 The American Association for Thoracic Surgery
Fifteen-month circulatory support for sustained ventricular fibrillation by left ventricular assist device
Motonobu Nishimura, MDa,*,
Masanori Ogiwara, MDa,
Masayuki Ishikawa, MDa,
Syogo Yatsu, MDa,
Ayumu Masuoka, MDa,
Nobuyuki Okamura, MDa,
Kazuhito Imanaka, MDa,
Masaaki Kato, MDa,
Haruhiko Asano, MDa,
Shunei Kyo, MDa
a Department of Cardiovascular Surgery, Saitama Medical School, Iruma-gun, Saitama, Japan
Received for publication February 13, 2003; accepted for publication March 24, 2003.
* Address for reprints: Motonobu Nishimura, MD, Department of Cardiovascular Surgery, Saitama Medical School, 38 Moro-hongo, Moroyama, Iruma-gun, Saitama 350-0495, Japan
nishimur{at}saitama-med.ac.jp
Patients with end-stage heart failure who receive support from a left ventricular assist system (LVAS) have been shown to tolerate malignant ventricular arrhythmia fairly well.1,2 The duration of malignant arrhythmia in the previous reports was at most a little more than 10 days. This report describes a patient who has been in sustained ventricular fibrillation (VF) for more than 1 year and has been supported by an LVAS without showing any symptoms.
Clinical summary
A 24-year-old woman, who demonstrated dilated cardiomyopathy, was first referred to us for heart failure and ventricular arrhythmia 5 years ago. At that time, she received the maximum medication and did well. She remained well until the age of 23 years, when she returned with profound heart failure and ventricular tachyarrhythmia resistant to medical therapy. Catecholamine was administered, and workup for cardiac transplantation was started. She experienced VF and was resuscitated using the percutaneous extracorporeal membrane oxygenator system (Emersave, Terumo, Tokyo, Japan). She was immediately brought to the operating room, where she underwent emergency placement of the Toyobo-NCVC LVAS (Toyobo, Osaka, Japan) with left ventricular drainage. Her postoperative course was essentially uneventful, but her ventricular arrhythmia continued despite aggressive antiarrhythmia medication. Three months after placement of the LVAS, she experienced VF again, which was resistant to external cardioversion (Figures 1A and 1B). Although her heart had been fibrillated, her LVAS flow was almost unchanged (3-4 L/min), and she showed no symptoms. Despite all the attempts to restore her original rhythm, she remained in VF. After several days, we stopped the attempts because she had been well with no symptoms, and further attempts may have caused embolism as the result of intracardiac thrombus. Since then, her heart has been in sustained VF for 15 months, but she has been ambulated, like other patients supported by an LVAS, while awaiting heart transplantation (Figure 2).
Although her right ventricle is not working, she has not demonstrated peripheral edema, pleural effusion, or ascites. Her pulmonary vascular resistance before LVAS placement was 2.44 Wood units. Her central venous pressure 3 months after demonstrating VF was approximately 10 mm Hg. Cardiac catheterization was not performed after sustained VF because of possible thrombus in her fibrillated heart.
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Figure 1B. Chest x-ray film 1 year after the onset of VF shows no pulmonary congestion but marked dilation of the right side of the heart.
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Discussion
Sustained VF is not a lethal arrhythmia for patients supported by an LVAS. In a report by Oz and associates,1 an LVAS was successful in supporting 9 patients who continued to experience malignant ventricular arrhythmia during device support. The arrhythmias lasted from 10 minutes to 12 days. The patients reported weakness, but none reported syncope. Fasseas and coworkers3 reported the successful use of an LVAS for the management of refractory ventricular arrhythmia. Nonetheless, early electrical cardioversion is indicated in patients demonstrating sustained VF with LVAS support because usually there is more than a 1 L/min decrease in device flow at the onset of VF.1
This is a rare case of a patient who has demonstrated sustained VF for more than 1 year and has been successfully supported by an LVAS. She is ambulatory without showing any symptoms, which is one of the reasons that we stopped attempting cardioversion. Otherwise, placement of a right ventricular assist device would be indicated in this setting as reported by Farrar and colleagues.4 There are 2 reasons why she remains in good shape in sustained VF while supported by an LVAS: (1) She has normal pulmonary vascular resistance (2.44 Wood units), which allows her a kind of Fontan circulation with an LVAS. (2) Her body size (body surface area of 1.42 m2) is small enough to maintain whole circulation with 1 Toyobo-NCVC LVAS, a pneumatically driven paracorporeal ventricular assist device developed in Japan. However, although she is able to walk around the hallway, her exercise capacity is very limited. Her latest data of peak oxygen consumption during exercise was 6.9 mL · min-1 · kg-1. Additional placement of a right ventricular assist device may improve her exercise capacity, but the risk of device-related complication would increase with biventricular assist. In Japan, the mean waiting period for a status-1 heart transplant candidate is more than 1 year. To minimize possible complication, univentricular assist is better for prolonged support lasting more than 1 year.
Experimentally, Takano and coworkers5 have shown the possibility of prolonged circulatory maintenance with an LVAS by studying goats in VF. To our knowledge, this is the first clinical case demonstrating that long-term circulatory support of a non-heart-beating patient is possible with left ventricular support only, when pulmonary vascular resistance is in the normal range.
References
- Oz MC, Rose EA, Slater J, Kuiper JJ, Catanese KA, Levin HR. Malignant ventricular arrhythmias are well tolerated in patients receiving long-term left ventricular assist devices. J Am Coll Cardiol. 1994;24:1688–1691[Abstract]
- Fasseas P, Kutalek SP, Kantharia BK. Prolonged sustained ventricular fibrillation without loss of consciousness in patients supported by a left ventricular assist device. Cardiology. 2002;97:210–213[Medline]
- Fasseas P, Kutalek SP, Samuels FL, Holmes EC, Samuels LE. Ventricular assist device support for management of sustained ventricular arrhythmias. Tex Heart Inst J. 2002;29:33–36[Medline]
- Farrar DJ, Hill JD, Gray LA Jr, Galbraith TA, Chow E, Hershon JJ. Successful biventricular circulatory support as a bridge to cardiac transplantation during prolonged ventricular fibrillation and asystole. Circulation. 1989;80(5 Pt 2):III147–151
- Takano H, Taenaka Y, Nakatani T, Noda H, Kinoshita M, Fukuda S, et al. Experimental studies of prolonged circulatory maintenance with a left ventricular assistance in cardiac arrested goats. Nippon Kyobu Gakkai Zasshi. 1989;37:411–422
