Effect of Acute Unloading Via Head-Up Tilt on QTc Prolongation in Patients With Ischemic or Non-Ischemic Cardiomyopathy

Grzywacz, Francis; Piacentino, Valentino; Marble, J.; Bozorgnia, Babek; Gaughan, John; Rothman, Steven A.; Margulies, Kenneth B.

doi:10.1016/j.amjcard.2005.08.064

Cited by 11 publications

(16 citation statements)

References 6 publications

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“…Post-LVAD arrhythmias have been attributed to a host of mechanisms including acute left ventricular unloading with pulsatile devices, 8 altered ventricular repolarization, 9 mechanoelectrical feedback from the LVAD motor, 10 alterations in calcium handing gene expression, 11 and so called “suction events.” 12 VAs in all patients are thought to originate from border-zone areas between cardiac scar tissue and normal myocardium where fibrosis alters the effective refractory period in the action potential and reentry circuits responsible for VA are generated. 13,14 Ventricular stretch is known to be arrhythmogenic, 15 so one may deduce that decompression of the failing ventricle with LVAD placement should decrease VAs.…”

Section: Discussionmentioning

confidence: 99%

Cryoablation during left ventricular assist device implantation reduces postoperative ventricular tachyarrhythmias

Mulloy

Bhamidipati

Stone

et al. 2013

The Journal of Thoracic and Cardiovascular Surgery

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Background The number of patients undergoing implantation of a HeartMate II left ventricular assist device (LVAD; Thoratec Corporation, Pleasanton, Calif) is rising. Ventricular tachyarrhythmia (VA) after placement of the device is common, especially among patients with preoperative VA. We sought to determine whether intraoperative cryoablation in select patients reduces the incidence of postoperative VA. Methods From January 2009 through September 2010, 50 consecutive patients undergoing implantation of the HeartMate II LVAD were examined. Fourteen of these patients had recurrent preoperative VA. Of those patients with recurrent VA, half underwent intraoperative cryoablation (Cryo: n = 7) and half did not (NoCryo: n = 7). Intraoperatively, patients underwent localized epicardial and endocardial cryoablation via LVAD ventriculotomy. Cryothermal lesions were created to connect scar to fixed anatomic borders in the region of clinical VA. Demographics, risk factors, intraoperative features, and outcomes were analyzed to investigate the feasibility of cryoablation. Results Thirty-day mortality remained low (n = 1, 2%) among all LVAD recipients. There were no differences in risk factors between groups except that preoperative inotropes were less prevalent in Cryo patients (P = .09). Compared with NoCryo, the Cryo group had significantly decreased postoperative resource use and complications (P<.05). Recurrent postoperative VA did not develop in any of the Cryo patients (P = .02). Conclusions Postoperative VA can be minimized by preoperative risk assessment and intraoperative treatment. Localized cryoablation in select patients offers promising early feasibility when performed during HeartMate II LVAD implantation. Further prospective analysis is required to investigate this novel approach.

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Section: Discussionmentioning

confidence: 99%

Cryoablation during left ventricular assist device implantation reduces postoperative ventricular tachyarrhythmias

Mulloy

Bhamidipati

Stone

et al. 2013

The Journal of Thoracic and Cardiovascular Surgery

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“…LVAD implantation, either as BTT or DT, has seen a steady rise in the United States during the past 6 years . A combination of underlying arrhythmogenic substrate from advanced cardiomyopathy and complex electrical and mechanical remodeling post‐LVAD implant predisposes these patients to development of de novo atrial and ventricular arrhythmias . In fact, in the study reported by HMII investigators, atrial and/or ventricular arrhythmias were noted in up to 56% of patients who received HMII LVADs for DT .…”

Section: Discussionmentioning

confidence: 99%

“…Left ventricular (LV) assist device (LVAD) therapy, either as bridge to transplantation (BTT) or as destination therapy (DT), has emerged as a promising treatment modality to maximize survival and minimize morbidity in patients with end‐stage heart failure . LVAD recipients, however, are at an increased risk for developing both atrial and ventricular arrhythmias, secondary to either pre‐existing abnormal electrical substrate or complex electrical remodeling following LVAD implantation . Persistent atrial arrhythmias, such as atrial flutter (AFL), while well tolerated by the LVAD‐supported left ventricle, can cause loss of atrioventricular (AV) synchrony resulting in impaired ventricular filling and decompensated right heart failure (RHF).…”

mentioning

confidence: 99%

Catheter Ablation of Atrial Flutter in Patients With Left Ventricular Assist Device Improves Symptoms of Right Heart Failure

Hottigoudar

Deam

Birks

et al. 2013

Congestive Heart Failure

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Persistent atrial flutter (AFL) in left ventricular assist device (LVAD) recipients can result in loss of AV synchrony, impaired ventricular filling and right heart failure (RHF). The authors report the largest series of HeartMate II (HMII) patients who developed AFL with decompensated RHF, which successfully resolved with AFL ablation. Eight patients with HMII LVAD (mean age, 57±12 years) had medically refractory AFL, with 7 developing de novo AFL after LVAD implant (onset range, 2 days-22 months post-implant). Three patients developed recurrent syncope, 2 had inappropriate implantable cardioverter-defibrillator shocks, and 6 had new or escalating need for inotropes. All had features of decompensated RHF. Seven patients underwent electrophysiology testing where mapping confirmed typical counterclockwise AFL (mean AFL cycle length, 252±49 ms) and radiofrequency ablation of cavotricuspid isthmus restored sinus rhythm in all patients. Complete resolution of symptoms and signs of RHF with improved quality of life were noted in all. No procedural complications were noted. During a mean follow-up of 9±5 months, all patients remained free of atrial flutter. Catheter ablation of AFL in LVAD patients is safe and highly effective, resulting in immediate and significant improvement in symptoms of RHF, and should be considered first-line therapy for AFL in these patients.

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“…Left ventricular assist devices (LVADs) have been used as a “bridge” to cardiac transplantation and as destination therapy in patients with advanced congestive heart failure. The early postoperative period after initiation of LVAD support of the failing human heart is associated with ventricular arrhythmias (VAs) 1–3 . This increased incidence of arrhythmogenesis after LVAD placement is still not well understood.…”

Section: Introductionmentioning

confidence: 99%

Ventricular Arrhythmias after Left Ventricular Assist Device Implantation

Refaat

Chemaly

Lebeche

et al. 2008

Pacing Clinical Electrophis

111

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Background Left ventricular assist devices (LVADs) have been used as a bridge to cardiac transplantation and as destination therapy in patients with advanced heart failure. The period after LVAD support is associated with ventricular arrhythmias (VAs) despite ventricular unloading and such VAs can have a detrimental effect on survival. Despite the increasing use of LVAD, little is known regarding post-LVAD VAs at the molecular level and in vivo. Methods Forty-two patients who received LVAD over a 24-month period were evaluated and grouped on the basis of the presence or absence of VAs during LVAD support. We completed a comparative microarray analyses between six patients who developed ventricular tachycardia (VT) or ventricular fibrillation (VF) after LVAD support and six patients who did not develop VAs after LVAD. Results VAs occurred in 15 patients (35.7%) during LVAD support at a median post-LVAD day of 25.2. VAs were strongly associated with nonusage of a β-blocker post-LVAD (odds ratio of 7.04, P-value = 0.001). Analysis of a subset of patients who had VT or VF after LVAD placement showed a decrease in the expression of connexin 43 (0.48 ± 0.07), Na+/K+–ATPase (0.60 ± 0.05), and voltage-gated K+ channel Kv4.3 (0.42 ± 0.04), and an increase in Na+/Ca2+ exchanger (2.2 ± 0.4) and the structural genes: Titin (2.1 ± 0.2), laminin (1.7 ± 0.4), calsequestrin (1.8 ± 0.5), skeletal muscle isoform of troponin T (5.1 ± 0.9), and skeletal muscle isoform of troponin I (3.9 ± 0.7). Conclusion After LVAD, the increased risk of VAs is strongly associated with nonusage of β-blocker postoperatively.

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Effect of Acute Unloading Via Head-Up Tilt on QTc Prolongation in Patients With Ischemic or Non-Ischemic Cardiomyopathy

Cited by 11 publications

References 6 publications

Cryoablation during left ventricular assist device implantation reduces postoperative ventricular tachyarrhythmias

Cryoablation during left ventricular assist device implantation reduces postoperative ventricular tachyarrhythmias

Catheter Ablation of Atrial Flutter in Patients With Left Ventricular Assist Device Improves Symptoms of Right Heart Failure

Ventricular Arrhythmias after Left Ventricular Assist Device Implantation

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