Arrhythmias and conduction disturbances after cardiac surgery.ppt

1、Arrhythmias and conduction disturbances after cardiac surgery,Anjan Gupta M.D. Milwaukee Heart Institute University of Wisconsin, M,Post cardiac surgery atrial arrhythmias,INCIDENCE OF ATRIAL FIBRILLATION OR FLUTTER AFTER CABG,Reference No. of Pts developing ECG Peak incidence and patients atrial fi

2、brillation documentation (days postop) Year studied or flutter,No Percent,Buxton, 1981 99 29 29 COM, Holter 3 Fuller, 1989 1666 473 28 COM, Holter 2 Yousif, 1990 100 19 19 COM, ECG 3 Leitch, 1990 5807 999 17 COM, ECG - Crosby, 1990 418 115 27 COM -,INCIDENCE OF ATRIAL FIBRILLATION OR FLUTTER AFTER C

3、ABG,Reference No. of Pts developing ECG Peak incidence atrial fibrillation and patients or flutter documentation (days postop) Year studied,No Percent,Klein, 1995 54 16 30 COM, ECG - Frost, 1995 128 38 30 COM, Holter - Frost, 1995 120 35 29 COM, ECG - Mendes,1995 168 57 34 COM, Holter 3 Augostini 96

4、 33 9 24 COM, ECG -,FACTORS ASSOCIATED WITH POST CABG ATRIAL FIBRILLATION AND FLUTTER,PREOPERATIVE FACTORS,Reference and No. of patients Significant predictive factors Year studied,Buxton, 1981 99 P wave duration Fuller, 1989 1666 Age, preop digoxin treatment Yousif, 1990 100 Myocardial ischaemia Le

5、itch, 1990 5807 Age, COPD, CRF, HTN, Preop diuretic, Preop beta blocker, CTR0.5, LM or 3 vessel CAD Crosby, 1990 1990 Age,FACTORS ASSOCIATED WITH POST CABG ATRIAL FIBRILLATION AND FLUTTER,PREOPERATIVE FACTORS,Reference and No. of patients Significant predictive factor Year studied,Klein, 1995 54 P w

6、ave duration on Signal averaged ECG Frost, 1995 102 Age, low vagal tone, ectopic SV beats, NSSVT Mendes, 1995 168 Severe RCA disease, age, male gender Augostini, 1995 33 Age Asher, 1996 2196 Age, Internal mammary conduit,FACTORS ASSOCIATED WITH POST CABG ATRIAL FIBRILLATION AND FLUTTER,PEROPERATIVE

7、FACTORS,Reference and No. of patients Significant predictive factor Year studied,Capucci,1987 50 Atrial conduction delay Yousif, 1990 100 Adj. coronary endarterectomy, topical cardiac cooling Leitch,1990 5807 More than 3 distal anastomosis Lowe, 1991 1991 Pace inducibility of atrial fibrillation,FAC

8、TORS ASSOCIATED WITH POST CABG ATRIAL FIBRILLATION AND FLUTTER,POSTOPERATIVE FACTORS,Reference and No. of patients Significant predictive factor Year studied,Fuller, 1989 1666 Postoperative beta blocker treatment, stroke Frost, 1995 128 atrial ectopics, SVT, atrial arrhythmias Augostini, 1995 33 sin

9、us cycle length, sinus node recovery time sinoatrial conduction time,SIGNIFICANT PREOPERATIVE PREDICTORS OF POSTOPERATIVE AFIB BY UNIVARIATE ANALYSIS,Predictor Relative Risk (95% CI) p - value,History of Atrial fibrillation 2.00 (1.75 - 2.30) 0.01 Valvular disease 1.50 (1.29 - 1.75) 0.01 CHF 1.44 (1

10、.26 - 1.65) 0.01 Vascular disease 1.27 (1.09 - 1.47) 0.01,Mathew et al , JAMA 1996 ; 276 : 300 - 306,MULTIVARIABLE PREDICTORS OF POSTOPERATIVE AFIB,Predictors Odds Ratio (95% CI) p - value,Hx of atrial fibrillation 2.28 (1.74 - 3.00) 0.01 Pulmonary Vein Venting 1.44 (1.13 - 1.83) 0.01 Male Sex 1.41

11、(1.09 - 1.81) 0.01 Age (per 5-y increase) 1.24 (1.18 - 1.31) 0.01,Mathew et al , JAMA 1996 ; 276 : 300 - 306,Length of stay in hospital after postop atrial arrhythmias,Creswell et al, Ann. of Thoac. Surg, 1993;56:539 - 49,Incidence of V-Fib, V-Tach and stroke associated with postop atrial arrhythmia

12、s,Creswell et al, Ann. of Thoac. Surg, 1993;56:539 - 49,Day of onset of atrial fibrillation after CABG,Klein et al.Am Ht Jn, 1995;129:895 - 901,Prevalence of A-fib according to age at operation,Leitch et al, Jn of Th. Card Surg,1990;100:338-342,Postoperative atrial fibrillation - Treatment,Ibutilide

13、 - a new drug for atrial Fibrillation and Flutter Class III antiarrythmic drug In a randomized trial was proven to be superior to placebo in converting post op afib ( Kowey et al ) A-flutter responds better than A-fib Adverse effects include development of Torsades,Atrial Fibrillation,Post CABG Afib

14、,Unstable,DC cardioversion,Recurrent,AA drugs,IV/oral procainamide, quinidine,Effective,Continue therapy,Ineffective,DC Cardioversion,Successful,Continue drug,Unsuccessful,Anticoag, new drug,Stable,Rate control,Persists 48 - 72 hrs,AA drugs,IV/PO procainamide, quinidine,Effective,Continue therapy,In

15、effective,DC Cardioversion,Successful,Continue drug,Unsuccessful,Anticoag, new drug,Anticoagulate,DC cardioversion,Add AA drugs if needed,MANAGEMENT OF POST CABG AFIB,Ventricular Tachyarrhythmias,Ventricular arrhythmias,EPIDEMIOLOGIC FEATURES Ventricular ectopy, including NSVT is seen in about 50% o

16、f patients after cardiac surgery Sustained VT and ventricular fibrillation occur rarely after cardiac surgery (0.4 - 1.4% reported in various studies),Ventricular arrhythmias,STUDIES OF VT AFTER CARDIAC SURGERY,Authors Patients Age (yr) Incidence EF Time from op,Kron et al 18 1.4% 38 15 2 days to 6

17、wks Topol et al 12 64 8 0.72% 39 10 2 days to 5 mth Sapin et al 13 62 11 44 16 5 hr to 7 days Tam et al 16 59 10 0.68% 25 4 1hr to 12 days Costeas et al 17 65 8 0.41% 37 11 24hr to 15 days,Ventricular arrhythmias,DIAGNOSIS 12 Lead ECG Postoperative telemetry monitoring Bipolar atrial recording with

18、epicardial wires,Ventricular Arrhythmias,Post CABG,Sust. Vent. Tachyarryth.,Ventricular Fibrillation,Defib. IV Lido, Proc, Brety,Identify/Treat ppt factors,No further AA therapy,Recurrence,Use other IV drugs eg Amio,EPS guided AA therapy,Unsuccessful,Consider ICD therapy,Successful,Continue the drug

19、s,Ventricular tachycardia,Unstable,Use V-Fib Protocol,Stable,IV Lido, Procain, Brety,Treat Ppt factors, Defib,Recurrence,Use V Fib recurr. protocol,No recurrence,No further therapy,MANAGEMENT OF POST CABG VT/VF,No Recurrence,Ventricular arrhythmias,Management of PVCs and NSVT Simple PVCs usually do

20、not require Rx Frequent PVCs can be suppressed by atrial pacing If frequent and symptom producing can be suppressed with beta blockers or AA No role for prophylactic lidocaine Patients with NSVT and EF 40% role of EP testing ?,Ventricular Arrhythmias,Variables POVD No POVD p - value n = 25 n = 84,Ag

21、e 62.8 9.7 56.2 7.5 0.0024 EF (%) 66.2 9.3 66.1 9.6 0.95 CrossClamp time (min) 55.6 15 57.4 21.1 0.70 By-pass time (min) 111.8 2.5 111.0 33.9 0.91 Preop beta blockers 21 72 0.91 Preop Ca Ch blockers 17 66 0.41 Previous MI 8 25 0.97 LM disease 8 17 0.34 LAD disease 22 74 0.74 Perioperative MI 4 7 0.4

22、6 PAD 11 19 0.30 Other Comp 2 13 0.53,Ferraris et al, J Cardiovasc Surg 1991;32:12 - 19,Post cardiac surgery arrhythmias,Potential causes and precipitating factors,Myocardial ischemia or infarction Hemodynamic instability Electrolyte abnormalities a) Hypokalemia, b) Hypomagnesemia Metabolic disturba

23、nces a) Acidosis, b) Alkalosis, c) Hypoxemia Drugs a) Sympathomimetics, b) Antiarrhythmics, c) Anesthetic Reperfusion effect Tissue trauma or inflammation, indwelling catheters Increase in catecholamines,Conduction Disturbances,Epidemiologic features and pathogenesis Transient conduction disturbance

24、s can occur in 4% to 58% of patients after CABG RBBB is the most frequently noted abnormality Incidence of isolated AV block is low after CABG but may be higher after associated valve surgery,Conduction Disturbances,Risk factors associated with Post CABG conduction disturbances,Studies Significant R

25、isk Factors,Emlein et al , 1993 age 64, LBBB Flack et al, 1992 use of cold cardioplegia Caretta et al, 1991 LM disease LAD stenosis, RCA occl,Conduction disturbances,Intraventricular conduction defects Incidence of postoperative fascicular conduction defects vary from 3-5% Longterm adverse prognosis

26、 is ascribed to appearance of new LBBB and nonspecific IVCD Postoperative LBBB has no immediate clinical impact and no specific Rx needed,Conduction disturbances,First Degree AV block Most commonly due to fibrosis of AV node or toxicity of medications such as beta blockers or calcium channel blocker

27、s Other causes include edema of AV node region after mitral and aortic valve replacement No specific therapy is usually needed,Conduction disturbances,Second-Degree AV block Mobitz Type I and Type II blocks are common after valve replacement surgery Drug effect or toxicity should be excluded as pote

28、ntial causes Temporary pacing may be needed depending on degree of AV block and HR as well as adequacy of lower escape rhythm,Conduction disturbances,Complete AV block May be secondary to cardioplegia washout during immediate postoperative period or as a consequence of antiarrhythmic drug therapy It may be seen after valve replacement secondary to trauma of surgical manipulation in the area of AV node or bundle of HIS,Conduction disturbances,Complete AV blo