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1 CASE PRESENTATION Ravi Dhanisetty, M.D. SUNY Downstate 23 July 2009

2 CASE PRESENTATION xx yr old female with chest pain for 3 days. Initially taken to outside hospital 3 days history of chest pain, shortness of breath and orthopnea. PMHx: HTN, DM EKG in ER Diffuse ST elevations and q waves in leads V1 to V5.

3 CASE PRESENTATION Emergently taken for cardiac catheterization. Complete occlusion of Left Anterior Descending Able to re-cannulate LAD and long segment stent placed. Intra-aortic aortic balloon pump placed. Anti-coagulated and monitored in ICU Over the course of 3 days patients condition i did not improve, required pressor support in addition to IABP.

4 CASE PRESENTATION Transferred to SUNY Downstate CT surgery service. Resuscitated, on multiple pressors, IABP, with blood pressure of 80/40s, CVP of 22, Cardiac index of and SVR of >1500. Echocardiogram: moderate to severe MR, minimal LV wall motion, EF 10%.

5 CASE PRESENTATION HD #2 despite maximal inotropic and IABP support, patient continued to be in shock with decreasing cardiac index Patient t underwent sternotomy t CABG with RSVG to LAD Left ventricular assist device implantation. Superior pulmonary vein to aorta

6 CASE PRESENTATION Post Operative course: Maintained on heparin drip with hourly ACT monitoring. Entirely dependent d on ventricular assist device for cardiac ouput. Remained on multiple pressors and intra- aortic balloon pump. Patients condition did not progress to multi-organ failure. POD #3 all intravenous lines and IABP were changed POD #6 patient transferred to Westchester for evaluation for destination therapy.

7 Mechanical Circulatory Support of the Heart: Ventricular Assist Devices Ravi Dhanisetty, M.D. SUNY Downstate 23 July 2009

8 Outline History Indications Patient selection / risk management Device components: Device selection Short term Long term Surgical technique Complications Clinical results Conclusions.

9 History 1953 Gibbon first successful cardiopulmonary bypass 1963 DeBakey first ventricular assist device for post op cardiac arrest 1966 DeBakey first successful VAD implanted post-operatively operatively 1994 FDA approval of VAD as bridge to transplantation ta spa tato 2001 FDA approval of VAD for destination therapy DeBakey 2005

10 Heart Failure Heart failure accounts for 250,000 deaths / yr Annual cost of heart failure $60 billion About $23 billion spent on inpatient treatment Leading cause of hospitalization of patients over 65 years old Despite optimal medical management 50% 5 yr mortality from diagnosis. Demand for cardiac transplantation vs low supply transplants per year.

11 Indications for VAD Placement Patient can no longer sustain adequate systemic oxygen delivery to maintain normal end-organ function despite maximal medical therapy. irreversible heart failure. Can be used for both acute and chronic forms of heart failure. DeBakey 2005.

12 Use of VAD Bridge to myocardial recovery Bid Bridge to cardiac transplantation t ti Destination therapy in patients not eligible for cardiac transplantation

13 Patient Selection One of the most critical determinants of successful outcomes with VAD therapy Operative risk weighted with potential benefit from device. Contraindications: Irreversible end-organ damage Severe and unrecoverable neurologic injury Systemic sepsis or bacteremia Aggarwal et al

14 Multivariate analysis of 130 patients undergoing LVAD Cumulative score of > 5 Operative mortality of 46 % < 5 12%. Other independent risk factors: Age > 65, multi-organ failure, right heart failure, acute infarction. Rao et al. 2003

15 Device Selection Anticipated endpoint of treatment ( (destination therapy, bridge to transplantation, or myocardial recovery) Expected duration of support Type of ventricular support (right, left, biventricular) Patient factors Body size and habitus, blood type, and preexisting contraindications to anticoagulation therapy Surgeon and institution experience with a device

16 SHORT TERM DEVICES Ease of implantation Short-term term bridge to recovery Bid Bridge to more permanent ventricular assistance. Disadvantages extracorporeal, require anticoagulation.

17 SHORT TERM DEVICES COUNTERPULSATION Intra-Aortic Balloon Pump CENTRIFUGAL / AXIAL PUMP Bio-medicus biopump, Sarns Centrifugal pump, St. Jude Lifestream centrifugal pump Percutaneous TandemHeart Percutaneous VAD (LA to fem art) Impella Recovery device PNEUMATIC PUMPS Abiomed BVS 5000i: FDA Approved

18 Intra-Aortic Balloon Pump 1968: first use by Kantrowitz and colleagues. Counterpulsation ti synchronized to either EKG or arterial waveforms Reduction in myocardial work (afterload reduction) Improvement in myocardial oxygen ( oxygen (augmentation of diastolic blood pressure and coronary perfusion pressure)

19 CENTRIFUGAL PUMPS Most commonly used, wide availability, ease of use, and relative low cost compared to other devices. Need systemic anticoagulation, not portable, and progressive development of interstitial edema secondary to capillary leak.

20 TandemHeart PERCUTANEOUS left VAD Extra-corporeal device Percutaneously placed venous catheter (21F) through atrial septum into left atrium under echo guidance. Outflow into femoral artery Can provide flows upto 4 L/min, unloads the heart, Ease of placement ideal for acutely decompensated heart failure, post CPR 30 day mortality of 44% - post-mi cardiogenic shock Bruckner BA. Et al Graphic Cardiac Assist Inc.

21 Impella PERCUTANEOUS Left VAD Use in high risk coronary interventions and for post cardiotomy shock Smaller, less expensive, easier to place (no trans-septal septal puncture). Used in low output cardiac output syndrome Improves survival patients with residual cardiac function of > 1 L /min. Windecker Siegenthaler et al

22 Abiomed BVS 5000i Only FDA approved device for acute postcardiotomy failure. Dual chambered pneumatically driven extracorporeal pump. Pulsatile flow up to 6 L/min Easily implanted, widely available, used in community yp practices for short term support and transport. Aggarwal et al

23 LONG TERM DEVICES Bridge to transplantation Destination therapy Smaller, intracorporeal devices, portable, reliable, greater battery life.

24 LONG TERM DEVICES Pulsatile Flow Heartmate XVE Novacor Left Ventricular Assist system Newer inflow conduits w/ less thromboembolic events Thoratec intracoporeal Ventricular Assist Device. Axial Flow Pumps (Non-Pulsatile) Micromed Debakey VAD Jarvik 2000 Heartmate II

25 Heartmate VE LVAD - Components Pulsatile Flow Rose et al

26 Heartmate VE LVAD FDA approved as a bridge to transplantation and for destination therapy Used in REMATCH trial. Pulsatile flow up to 10 L /min with pump placed in pre- peritoneal pocket Need BSA of > 1.5 m2 Textured polyurethane internal surfaces that t encourages a pneudo-intima formation so no systemic anti-coagulation. Extensive experience with over 4000 units implanted with duration up to 1800 days. Aggarwal et al. 2008

27 Novacor Left Ventricular Assist System First successful bridge to transplantation. t ti Similar to Heartmate, except needs anticoagulation. Excellent long term durability with low rates of device failure or neurologic dysfunction. Device used in INTREPID trial. Aggarwal et al

28 THORATEC PARACORPOREAL VAD Para-corporeal placement of pump allows use in smaller patient (as small as 17 kg). Used in 2850 patients with >60 % survival to transplantation Kukuy et al

29 Axial Flow Pumps Rotating impeller continuous non-pulsatile flow. Smaller, use less energy, more durable, easy to implant, and used in smaller patients Disadv lacks backup mechanisms, hemolysis secondary to shear forces, potential for creating negative intraventricular pressure and device thrombosis, air embolism, or arrhythmias. Effect of non-pulsatile flow on end-organ function is not known. Currently undergoing clinical trials. Micromed Debakey VAD Jarvik 2000 Heartmate II Aggarwal et al

30 MICROMED-DEBAKEY DEBAKEY VAD (1980s) developed w/ collaboration with NASA 3 x 1.2 in, 95 gms. Need anticoagulation Flow of 5 L/min Portability allows for greater patient rehabilitation. Kukuy et al DeBakey

31 Implanted via Left thoracotomy Actual pumping chamber is implanted within the left ventricle Jarvik 2000 Newer version with transcutaneous energy transfer. Aggarwal et al

32 Newer-generations and future Newer devices: devices Magnetic levitation technology Advanced energy systems Smaller control consoles. Incor Left VAD: magnetically-actuated actuated axial flow pump Heartmate III: magnetically suspended centrifugal pump Aggarwal et al. 2008

33 POST-OPERATIVE OPERATIVE CARE Ensure proper/optimal device function Aggressively treat right heart failure. Decrease excessive afterload Antibiotic prophylaxis for 48 to 72 hours Optimize i fluid balance w/ aggressive diuresis Early anticoagulation once mediastinal bleeding has subsided. Aggarwal et al

34 Complications Bleeding early and late Infection Most common cause of mortality Up to 50% of patients Staphylococcus, Pseudomonas, Enterococcus,, and Candida Thrombo-embolic events Right Heart Failure Device Failure Immunologic Effects and Allosensitization Progressive defects in cellular immunity increased risk of infection B-cell activation sensitization to HLA antigens (66% to 6% prior to transplant) t) John et al

35 Clinical Trials REMATCH (2001) INTrEPID (2007) Evaluated the use of Ventricular Assist Devices in patients with end-stage heart failure who are ineligible for transplantation.

36 REMATCH Trial 129 patients with end-stage heart failure who were not eligible for transplantation. Randomized to either LVAD or optimal medical therapy. Primary end point mortality LVAD Group: 48% reduction in mortality from any cause Higher quality-of-life and functional status Rose et al

37 Rose et al

38 INTrEPID Trial 55 inotrope dependent patients with end-stage heart failure who were ineligible for transplantation randomized to LVAD or medical therapy Primary end-point 6 month mortality Conclusion LVAD provided survival advantage Rogers et al

39 INTrEPID Trial Rogers et al

40 INTrEPID Trial Adverse Outcomes Rogers et al

41 Conclusions Mechanical circulatory support is an important therapeutic option in treatment of both acute and chronic heart failure. Currently, indications are limited for use as a bridge to recovery and transplantation. In certain situations (end-stage heart failure) can be a useful alternative to medical treatment. Devices still have many limitations due to excessive frequency of adverse events, which may decrease with newer technology.

42 Questions 1. Most common complication of LVAD insertion a. Bleeding b. Infection c. Thrombo-embolic events d. Device failure 2. Mechanical circulatory support can be used for all of the following except. a. As a bridge to recovery b. Bridge to transplantation c. Destination therapy d. Enhance normal cardiac function

43 Questions 3. Which of the following is an indication for mechanical circulatory support. a. Heart failure requiring diuretic therapy b. Cardiogenic shock in a comatosed patient c. Heart failure with persistent dyspnea on excertion d. Cardiogenic shock that is refractory to inotropes and IABP 4. Which of the following factors affect device selection: a. Goal and duration of therapy b. Surgeon and institution experience c. Patient factors including body habitus and size d. All of the above

44 References Aggarwal S et al. Long-Term Mechanical Circulatory support. Cardiac Surgery in the Adult. 3 rd Ed. New York: McGraw-Hill, 2008: Bruckner, BA. Et al. Clinical experience with TandemHeart Percutaneous VAD as a bridge to cardiac transplantation. Tex Heart Inst J. 2008; 35(4): DeBakey, ME. Development of Mechanical Heart Devices. Ann Thorac Surg 2005; 79. John R, Lietz K, Schuster M, et al: Immunologic sensitization in recipients of left ventricular assist devices. J Thorac Cardiovasc Surg 2003; 125:578. Kukuy EL. Et al. Long-Term Mechanical Circulatory support. Cardiac Surgery in the Adult. 3 rd Ed Rao V, Oz MC, Flannery MA, et al: Revised screening scale to predict survival after insertion of a left ventricular assist device. J Thorac Cardiovasc Surg 2003; 125:855 Rogers JG, Butler J, Lansman SL, et al. Chronic mechanical circulatory support for inotrope- dependent heart failure patients who are not transplant candidates. Results of the INTrEPID trial. J Am Coll Cardiol 2007; 50: Rose EA, Gelijns AC, Moskowitz AJ, et al: Long-term use of left ventricular assist device for end- stage heart failure. N Engl J Med 2001; 345:1435. Siegenthaler et al. Impella Recover microaxial left VAD reduces mortality for postcardiotomy failure: a three-center t experience. JTh Thorac Cardiovasc Surg 2004; 127: Windecker, S. Impella Assisted High risk percutaneous coronary intervention. Kar Med. 2005; 8: Zevitz, ME. Heart Failure. emedicine, 2006.