Is Mobitz type I XXXX benign in adults?

@entity1 @entity713 @entity13610 @entity299 @entity1168
OBJECTIVE: To assess the need for pacing in adults with chronic Mobitz type I second degree @entity713 (Mobitz I). DESIGN: Prospective study. SETTING: District general hospital. @entity1 : 147 subjects aged > or = 20 years (age cohorts 20-44, 45-64, 65-79, and > or = 80) with chronic Mobitz I without second degree Mobitz II or third degree (higher degree) block on entry, seen from 1968 to 1993 and followed up to 30 June 1997. Sixty four had @entity299 . The presence of symptomatic @entity1168 was defined as highly likely in 47 @entity1 (class 1); probable in 14 (class 2); and absent in 86 (class 3). INTERVENTIONS: Pacemakers were implanted in 90 @entity1 for the following indications: symptoms in 74 and prophylaxis in 16. MAIN OUTCOME MEASURES: The main outcome measure was death, with conduction deterioration to higher degree block or symptomatic @entity1168 the alternative measure. RESULTS: Five year survival to death was reduced in unpaced @entity1 relative to that expected for the normal population (overall mean (SD) 53.5 (6.7)% v 68.6%, p < 0.001; class 3, 54.4 (7.3)% v 70.1%, p < 0.001). Paced @entity1 fared better than unpaced (overall (mean (SD) five year survival 76.3 (4.5)% v 53.5 (6.7)%, p = 0.0014; class 3, 87.2 (5.4)% v 54.4 (7.3)%, p = 0.020; and @entity299 , 68.2 (7.6)% v 44.0 (9.9)%, p < or = 0.0014). There were no deaths in the < 45 cohort. Survival to first outcome (main or alternative) was further reduced to 31.7 (5.0)% in 102 @entity1 unpaced initially and 34.2 (5.7)% in class 3. Only the 20-44 cohort and @entity1 with @entity13610 had > 50% survival. CONCLUSION: Mobitz I block is not usually benign in @entity1 > or = 45 years of age. Pacemaker implantation should be considered, even in the absence of symptomatic @entity1168 or @entity299 .
