BME 301Progression of Heart DiseaseReview of Last TimeWhich one is a healthy heart?Slide 5Slide 6Slide 7Artificial Heart - HistoryHistory of Artificial HeartSlide 10Slide 11Slide 12AbioCor Artificial HeartSurgical ProcedureSlide 15Clinical Trial of AbioCorSlide 17Slide 18Consent FormPlanning a Clinical TrialExample – Planning a Clinical TrialSample Size CalculationTypes of Errors in Clinical TrialSlide 24How do we calculate n?Drug Eluting Stent – Sample SizeAssignments Due Next TimeBME 301Lecture NineteenProgression of Heart DiseaseHigh Blood PressureHigh Cholesterol LevelsAtherosclerosisIschemiaHeart AttackHeart FailureReview of Last TimeWhat is heart failure?Occurs when left or right ventricle loses the ability to keep up with amount of blood flowhttp://www.kumc.edu/kumcpeds/cardiology/movies/sssmovies/dilcardiomyopsss.htmlHow do we treat heart failure?Heart transplantRejection, inadequate supply of donor heartsLVADCan delay progression of heart failureArtificial heartWhich one is a healthy heart?Which one is a healthy heart?Heart FailureWhich one is a healthy heart?Heart Failure Heart FailureWhich one is a healthy heart?Heart Failure Heart FailureAtrial FibrillationHealthy HeartArtificial Heart - HistoryFirst artificial heart implanted in 1969No more human trials until the 1980s…History of Artificial Hearthttp://www.cbsnews.com/stories/2004/05/27/earlyshow/contributors/emilysenay/main620068.shtmlJune 2001http://discover.npr.org/features/feature.jhtml?wfId=1123833August 2001http://discover.npr.org/features/feature.jhtml?wfId=1127758November 2001http://discover.npr.org/features/feature.jhtml?wfId=1133260 http://images.usatoday.com/news/_photos/2001-11-30-heartguy.jpgHistory of Artificial Heart•1958:•Designed by Drs. Willem Kolff and Tetsuzo Akutsu •Polyvinyl chloride device •Sustained a dog for 90 minutes•1965:•Dr. Willem Kolff •Silicone rubber heart•Tested in a calfhttp://www.accessexcellence.org/WN/graphics/jarvik.jpg http://www.abiomed.com/images/prodtech/kolff65.jpgHistory of Artificial Heart•1969:•Dr. Domingo Liotta•First to be implanted in human as bridge to transplant •Patient survived for 3 days with artificial heart and 36 hours more with transplanted heart•1982:• Drs. Willem Kolff, Donald Olsen, and Robert Jarvik, •Jarvik-7•First to be implanted in a human as destination therapyhttp://www.abiomed.com/images/prodtech/liotta.jpghttp://static.howstuffworks.com/gif/artificial-heart-abiocor-diagram.gif http://www.ps-lk3.de/images/ABIOCOR.JPGAbioCor Artificial Hearthttp://www.heartpioneers.com/newsimages.html#Cost: $70-100khttp://www.cardiocaribe.com/newsite/images/articulos/feb02/abiocor_hand.jpgSurgical ProcedureSurgeons implant energy-transfer coil in the abdomenThe chest is opened and patient is placed on a heart-lung machineSurgeons remove the right and left ventricles of native heart. This part of the surgery takes two to three hoursAtrial cuffs are sewn to native heart's right and left atriaA plastic model is placed in the chest to determine the proper placement and fit of the heart in the patientGrafts are cut to an appropriate length and sewn to the aorta and pulmonary arteryThe AbioCor is placed in the chest. Surgeons use "quick connects" -- sort of like little snaps -- to connect heart to the pulmonary artery, aorta and left and right atria. All of the air in the device is removedThe patient is taken off the heart-lung machinehttp://www.pbs.org/wgbh/nova/eheart/transplantwave.html `http://www.louisville.edu/hsc/medmag/ss01/images/abio-prep.gif http://www.heartpioneers.com/images/news/implant_thumb.jpgClinical Trial of AbioCorGoals of Initial Clinical TrialDetermine whether AbioCor™ can extend life with acceptable quality for patients with less than 30 days to live and no other therapeutic alternative To learn what we need to know to deliver the next generation of AbioCor, to treat a broader patient population for longer life and improving quality of life.Clinical Trial of AbioCorPatient Inclusion Criteria (highlights)Bi-ventricular heart failure Greater than eighteen years old High likelihood of dying within the next thirty daysUnresponsive to maximum existing therapies Ineligible for cardiac transplantation Successful AbioFit™ analysis Patient Exclusion Criteria (highlights)Heart failure with significant potential for reversibility Life expectancy >30 days Serious non-cardiac disease Pregnancy Psychiatric illness (including drug or alcohol abuse) Inadequate social support systemClinical Trial of AbioCorClinical Trial EndpointsAll-cause mortality through sixty days Quality of Life measurementsRepeat QOL assessments at 30-day intervals until death Number of patients Initial authorization for five (5) implants Expands to fifteen (15) patients in increments of five (5) if 60-day experience is satisfactory to FDAConsent Formhttp://www.abiomed.com/Fabiocor.htmlhttp://www.awpagesociety.com/public/cases/ABIOMED_1-Case.pdfPlanning a Clinical TrialTwo arms:Treatment groupControl groupOutcome:Primary outcomeSecondary outcomesSample size:Want to ensure that any differences between treatment and control group are realMust consider $$ availableExample – Planning a Clinical TrialNew drug eluting stentTreatment group:Control group:Primary Outcome:Secondary Outcomes:Sample Size CalculationThere will be some statistical uncertainty associated with the measured restenosis rateGoal:Uncertainty << Difference in primary outcome between control & treatment groupChoose our sample size so that this is trueTypes of Errors in Clinical TrialType I Error:We mistakenly conclude that there is a difference between the two groups, when in reality there is no differenceType II Error:We mistakenly conclude that there is not a difference between the two, when in reality there is a differenceChoose our sample size:Acceptable likelihood of Type I or II errorEnough $$ to carry out the trialTypes of Errors in Clinical TrialType I Error:We mistakenly conclude that there IS a difference between the two groupsp-value – probability of making a Type I errorUsually set p = 1% - 5%Type II Error:We mistakenly conclude that there IS NOT a difference between the twoBeta – probability of making a Type II
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