Recommended Guidelines for Monitoring and Supervision of North Carolina Phase II/III Cardiac Rehabilitation Programs

Probably the most widely discussed and controversial topic in cardiac rehabilitation has been, and continues to be, the degree of monitoring and supervision required for patients of Phase II/III cardiopulmonary rehabilitation programs (CRPs). Phase II/III practices currently range from no continuous telemetered electrocardiographic monitoring (CTEM) for any patients1, 2 to use of CTEM for 3 weeks to 6 months for patients who have undergone percutaneous transluminal coronary angioplasty (PTCA). 3-6 Many programs routinely use CTEM on all Phase II patients for up to 36 exercise sessions, regardless of the individual level of cardiovascular risk. Because of variations in published risk stratification criteria, variations in the definitions of Phase II, III, and IV programs, individual beliefs on degree of monitoring, and the certainty that some high-risk patients will remain clinically high risk for years, the length and type of cardiovascular monitoring for risk stratified patients has become a clouded issue. The degree of monitoring and supervision appears to vary by the facility, even in states with well-defined CRP guidelines. 6-10 This is due to many factors, including: (1) patient cost for CTEM ranging from 30-110 per session; (2) a lack of data on the optimal duration of electrocardiographic (ECG) monitoring before independent cardiac exercise; (3) the qualifications and number of staff available for supervision; (4) individual beliefs for risk stratification; (5) current Medicare and insurance reimbursement patterns; and (6) the uncertainty of proposed health-care practices and reimbursement patterns in the future. Currently, only 11% to 15% of cardiac patients actually participate in a formal supervised CRP, 11, 12 with a 30% to 40% dropout rate within the first 6 months. 13 Given these dismal statistics, unsupervised gymnasium or home exercise programs (with or without transtelephonic ECG monitoring) is advocated for low to moderate risk patients if accessibility to a formal CRP is impractical. 14-21 The use of transtelephonic exercise monitoring for patients who exercise at home, in community centers, or in university settings has become more prevalent and may provide for greater participation for patients of all risk strata. Low-risk patients with myocardial infarction and patients with coronary artery bypass graft (CABG) surgery can exercise safely, improve aerobic capacity, and receive other beneficial effects from a home or gymnasium program. 16, 17, 20-26 It is recommended that home exercisers be properly screened and have periodic re-evaluation of their cardiac risk factors. 1, 20, 27 Although unsupervised exercise has been recommended by some for patients who may be considered at high risk, 28, 29 including those with chronic heart failure, 30 the risks and/or benefits of unsupervised exercise in the home or gymnasium setting for high-risk patients have not yet been thoroughly examined. 31 There are also legalities that must be considered for all cardiac patients who engage in unsupervised exercise programs. 15, 32, 33 Disadvantages to unsupervised exercise are that patients often become noncompliant with home exercise or fail to perform exercises appropriately because of a lack of regular feedback from CRP staff on proper exercise procedures. Patients who perform home exercise also miss the group camaraderie, group and staff support, and the ongoing cardiac disease education associated with a formal CRP. The pros and cons of unsupervised cardiac exercise are presented in Table 1. Risk stratification has enhanced patient classification in CRPs based on the likelihood of future cardiac events, making it easier to determine who should have closer monitoring and supervision. Guidelines, position statements, and risk stratification classifications presented by the American Association of Cardiovascular and Pulmonary Rehabilitation (AACVPR), 34 American College of Sports Medicine (ACSM), 35, 36 American College of Cardiology (ACC), 37 American College of Physicians (ACP), 38 American Heart Association (AHA), 39 the Department of Health and Human Services, 40 the North Carolina Cardiopulmonary Rehabilitation Association (NCCRA), 10, 41 and others have provided useful recommendations for cardiovascular monitoring in CRPs. However, because of the variation in definitions of cardiovascular risk presented by these and other organizations and the ambiguity regarding CTEM in patients of varying risk strata, there still remains wide discrepancy in monitoring/supervision practices among CRPs. In the 1995 AACVPR “Guidelines for Cardiac Rehabilitation Programs”34 and the U. S. Department of Health and Human Services' “Clinical Practice Guidelines for Cardiac Rehabilitation, ”40 broad minimal guidelines for ECG monitoring are presented which encourage risk stratification and patient self-monitoring. However, issues specific to risk stratification and duration of ECG monitoring are not addressed. Monitoring in CRPs has been discussed extensively14, 42-49 and due to a wide variation in beliefs and practices, many of these issues may never be fully resolved or result in overall program uniformity. To address monitoring and safety issues, North Carolina developed state-wide standards of practice, which include vocational, psychosocial, nutritional, and exercise therapies in 1983 (revised in 1995) 10 and a peer review process is currently used to certify and recertify CRPs. Programs may be awarded either full certification status, provisional certification status, or have their certification suspended or revoked if they fail to assure patient safety with proper emergency procedures or fail to adhere to proper monitoring/supervision standards. Specifications for emergency equipment and procedures are well-defined in the rules and coincide with guidelines presented by the AACVPR, 34 ACSM, 35 and AHA. 39, 40 The minimal standards for monitoring and supervision of Phase II/III programs in North Carolina are stated as follows: 10 Rule. 0507 (B) “At the discretion of the medical director, the patient may be monitored continuously or intermittently through the use of electrocardiography while performing the exercise therapy” (page 14). Rule. 0507 (D) “A minimum of two staff members must be present during the exercise therapy session. A staff-to-patient ratio in the exercise therapy session shall be at least 1: 10. A staff-to-patient ratio in a telemetry-monitored exercise therapy session shall be at least 1: 4” (page 14). Rule. 0903 (A) “Two medical personnel must be present during the exercise therapy session. The medical personnel must consist of the supervising physician and at least one additional medically trained person, who has the written approval of the medical director” (page 23). Given the wide range of practices that have been derived from these rules, a special task force of the NCCRA has developed a more detailed framework for monitoring and supervision of Phase II/III CRPs based upon current literature and trends. These recommendations have been reviewed and approved by the Exercise Science and Executive committees, which consists of staff members from many North Carolina CRP's. The information provided in this paper does not supersede or substitute for any part of the published state guidelines and should be viewed as recommended rather than absolute guidelines. For the purposes of this paper, we have adapted the definitions of the various phases of cardiac rehabilitation (Phases II-IV) from the AACVPR guidelines34 and Hall. 50 Phase II (immediate outpatient): Physician-referred exercise and behavior change therapy that is ideally initiated within 2 to 3 weeks after hospital discharge. Phase II programs may use intensive monitoring and supervision, including ECG monitoring for some patients. Phase III (intermediate outpatient): Physician-referred exercise and behavior change that begins when the patient has stabilized and that does not require continuous or frequent intermittent ECG monitoring. There is a continued emphasis on endurance exercise training and behavior change at this level. Phase III has less supervision than Phase II and more supervision than Phase IV. Phase IV (maintenance outpatient): The staff have determined that the patient's ability to maintain achieved outcomes and continue to work on optimal health practices under minimal surveillance is sufficient. This paper will not address Phase IV monitoring and supervision guidelines, as these have been presented elsewhere. 41 In North Carolina, Phase II programs often are conducted for 8 to 12 weeks, although some patients may require longer intensive monitoring and/or supervision. Phase III often encompasses the period of 12 weeks to 1 year. Phase IV is often categorized as the maintenance period after 1 year of formal CRP participation. It should be noted that these time definitions are broad and will vary by the program. Risks of Exercise Training To analyze the need for monitoring and supervision in CRPs, the level of risk of untoward events associated with exercise must first be examined. Sudden cardiac death with exercise is rare in apparently healthy populations and is usually the result of congenital abnormalities or cardiomyopathies (often hypertrophic cardiomyopathy) in persons 35 years of age. 39, 51-53 The vast majority of sudden cardiac death cases are arrhythmic in origin. 44, 54, 55 Exercising with undetected CAD, rather than exercise alone, is usually the precipitator of potentially lethal arrhythmias and/or sudden death. 52, 56 From the early 1960s to late 1970s, untoward events were reported during vigorous exercise in joggers, runners, 56-60 and patients of cardiac exercise programs. 55, 61, 62 Between 1975 and 1980 Thompson and colleagues56 reported 1 death for every 7, 620 male joggers aged 30 to 64. This was equal to an hourly death rate seven times greater than that observed during more sedentary activities. However, if men with known CAD were excluded, the death rate dropped to only 1 death per year for every 15, 200 joggers. Larger retrospective studies have shown the incidence of cardiac arrest or sudden death during exercise to be extremely low in both apparently healthy63-66 and cardiac67-70 populations. Kohl and co-workers52 summarized the results of these and other studies and reported mortality rates ranging from 0. 0 to 2. 0 per 100, 000 person-hours for apparently healthy individuals who performed both low- and high-intensity exercise. Strenuous physical activity has been shown to be associated with a transient increase in the risk of acute myocardial infarction in habitually sedentary populations. 55, 68, 71, 72 Many have speculated that habitual exercise provides protection against the triggering of myocardial infarction. 68, 71-75 Willich and colleagues72 reported that men and women who exercised less than 4 times per week had a relative risk of myocardial infarction of 6. 9, whereas those who exercised >4 times per week had a relative risk of only 1. 3. Similarly, Mittleman and associates71 found that the more one exercised, the lower the risk of acute myocardial infarction. Men and women who exercised 5 times per week had a relative risk of myocardial infarction of 107, 19. 4, 8. 6, and 2. 4, respectively. In 1984, Siscovick and associates68 reported similar findings showing that while risk of cardiac arrest is transiently increased during vigorous exercise, men who performed habitual vigorous exercise had a 40% lower relative risk of cardiac arrest compared to sedentary men. In this study, the risk of having a cardiac arrest during exercise was 56 times greater for sedentary men, yet only 5 times greater during exercise for men who had high levels of habitual physical activity (>140 minutes per week). In 1989, Blair and colleagues75 reported a low relative risk (28%) of having a fatal cardiac arrest for individuals who exercised regularly compared to those who did not. Thus, physical activity may lower the level of cardiovascular risk in habitually active populations. Most agree that exercise is very safe for healthy populations and properly screened cardiac participants and that the benefits of exercise clearly outweigh the risks. Exercise Complications in Cardiac Patients In general, well-designed studies of exercise complications in CRP participants are few and have shown varied results. Earlier studies reported cardiac arrest rates ranging from approximately 1/6, 000 patient-hours to 1/32, 000 patient-hours of exercise. 55, 61, 62, 69, 76-81 In a 13-year retrospective study of CRP participants, Hossack and Hartwig55 reported 25 cardiac arrests in 2, 464 patients during 374, 616 hours of supervised exercise (overall incidence of 1 arrest per 14, 985 hours) at the Cardiopulmonary Research Institute (CAPRI) rehabilitation program between 1968 and 1981. Of these arrests, 16 occurred during exercise and 9 during the cool-down period. All occurred in males and 100% were successfully resuscitated. Of the 25 arrests, 12 occurred in patients who had been enrolled >12 months. Similar rates of cardiac arrest during CRP exercise have been reported by Fletcher and Cantwell62 (1 arrest per 15, 000 hours of exercise) and Leach and coworkers78 (1 arrest per 12, 000 hours). Hossack and Hartwig55 determined that the three greatest predictors of cardiac arrest were: (1) marked ST-segment depression on the ECG; (2) an above average exercise capacity; and (3) a record of poor compliance with exercise intensity guidelines (i. e. , intensity violators). Data from Schuler and associates82 reinforce the finding that intensity violators are at greater risk of developing cardiovascular complications, as they reported that three patients who exceeded their prescribed target heart rate zone developed life-threatening arrhythmias during exercise. In one of the largest reported surveys of multiple centers, Haskell69 accumulated data on 13, 570 CRP participants from 30 programs between 1960 and 1977 (1, 629, 634 patient-hours of supervised exercise). In this study, 61 major cardiovascular complications were reported that included 50 cardiac arrests and 7 myocardial infarctions. The incidence of cardiovascular complications from these centers was lower than previously reported: 1 arrest per 32, 593 exercise hours; 1 myocardial infarction per 232, 809 exercise hours; and 1 fatality per 116, 402 exercise hours (mortality rate of 0. 61 per 100, 000 hours of exercise). The overall complication rate (fatal and nonfatal) was 1 event for every 26, 715 patient-hours. Forty-two (84%) of the 50 subjects who suffered a cardiac arrest were successfully resuscitated. Forty of 61 (66%) major complications occurred during either warm-up or cool-down exercise. The two programs which reported using CTEM for all patients during exercise had an overall complication rate (fatal or non-fatal) of 1 event per 117, 333 patient-hours of exercise, significantly lower than the 28 programs that did not conduct CTEM which averaged 1 event for every 22, 028 patient-hours of exercise. Haskell69 speculated that the lower complication rates observed in the programs that used CTEM may have been because of other program characteristics, such as closer medical supervision of lower exercise intensities. In 1986, Van Camp and Peterson67 reported significantly fewer cardiovascular complications during exercise than had previously been reported. These investigators reported a total of 29 complications during CRP exercise (21 cardiac arrests and 8 myocardial infarctions) which included 3 fatal events during 2, 351, 916 hours of outpatient exercise training. This was equivalent to 1 cardiac arrest per 111, 996 patient-hours (8. 9 arrests per 1, 000, 000 exercise hours) ; 1 myocardial infarction per 293, 990 patient-hours (3. 4 infarctions per 1, 000, 000 hours of exercise, similar to Haskell's data) ; and 1 fatality per 783, 972 patient-hours of exercise (1. 3 fatalities per 1, 000, 000 exercise hours or a mortality rate of 0. 13 per 100, 000 hours of exercise). Combining the 21 cardiac arrests and 8 myocardial infarctions yielded an overall complication rate of 1 per 81, 101 patient-hours of exercise. Of the 21 patients who experienced a cardiac arrest, 18 (86%) were successfully resuscitated. Twelve of 20 cardiac arrests (60%) occurred during the exercise session, 6 (30%) occurred during the immediate recovery period, and 2 (10%) occurred 30 to 60 minutes after the exercise session. 44 There was no significant difference in the frequency of events among Phase II-IV patients considering either the size of the program, the extent of ECG monitoring, or compliance to exercise. Furthermore, of the 167 separate programs in the study, 144 (86%) reported no major cardiovascular complications during the study period of 1980-1984. Similar nonfatal complication rates in cardiac patients have been reported by Shephard and colleagues70 at the Toronto Rehabilitation Centre (1 cardiac arrest per 113, 583 patient-hours of exercise) and Meyer43 from Cardiac Treatment Centers (1 complication per 122, 000 patient-hours of exercise). From these investigations, it appears that mortality rates in CRPs range from 0. 13 to 0. 61 per 100, 000 person-hours of supervised cardiac exercise. 52, 67, 69 This is equivalent to 3 deaths per 2, 351, 916 person-hours67 and 10 deaths per 1, 629, 634 person-hours69 of exercise, respectively. Thus, it appears that although the risk of having a serious cardiac event may be increased slightly during supervised exercise, the risk of sudden death is not greater for CRP participants. Greenland and Pomilla46 performed a weighted average of cardiac risk in CRPs from 8 studies that indicated 1 fatality per 386, 908 patient hours of exercise or a mortality rate of 0. 26 per 100, 000 patient-hours, which is similar to mortality rates reported in studies of apparently healthy exercisers. 56, 64 Haskell81 determined from previously cited studies that the risk of having a cardiac arrest during supervised CRP exercise is only once every 4 years. Clearly, the incidence of cardiac arrest has decreased among CRP participants from the 1960s to the 1980s. Whether having patients continuously ECG monitored improves patient safety and reduces the risk of cardiovascular complications has not been formally studied and remains to be seen. The incidence of exercise related cardiovascular complications have been reported to be low in North Carolina and California programs that use little or no CTEM. At the Wake Forest CRP in Winston-Salem, North Carolina, 11 cardiovascular complications requiring physician assistance have occurred during supervised exercise in more than 1, 700 patients (mean age 62 years) between 1975 and 1995. 2 These were as follows: eight instances of cardiac arrest (all successfully resuscitated) ; two instances of sudden onset bradycardia; and one myocardial infarction (post-exercise). Of these complications, nine occurred in Phase IV (maintenance) participants and two occurred in Phase II participants. This program typically enters Phase II or “beginner” patients 3 to 6 weeks after a cardiac event and retains a large number of these patients in their maintenance program. No fatalities have been reported in this CRP since its inception. This particular program does not use CTEM, but rather performs intermittent “quick-check” defibrillator ECG checks on a daily or weekly basis for most patients. Medical supervision (staff-to-patient ratio of at least 1: 10) is provided by exercise physiologists, a nurse, graduate students and an attending physician. 83 The finding at Wake Forest that cardiovascular complications can occur as or more frequently in Phase IV (maintenance) participants as in Phase II participants has been supported by others. 44, 55, 67, 82 At the Mecklenburg Cardiac Rehabilitation Center in Charlotte, North Carolina, six exercise-related complications requiring physician assistance and/or emergency medical team response have occurred in more than 2, 000 Phase II-IV patients between March 1984 and December 1995 (unpublished data). These were three instances of myocardial infarction resulting from acute thrombosis of angioplastied vessels in early morning exercise sessions and one myocardial infarction and two instances of cardiac arrest in afternoon sessions. All cardiac arrests and one myocardial infarction occurred during prescribed target exercise and two myocardial infarctions occurred during cool-down exercises. Each case was handled successfully and all occurred in Phase IV participants. In this program, CTEM is used only for selected high risk Phase II patients (usually for a maximum of 2 to 3 weeks) and no patients were using CTEM at the time of their complications. At the Cardiac Therapy Foundation of Palo Alto, California (formerly YMCArdiac Therapy), CTEM has never been used for any Phase II-IV patients, including those considered to be at high risk. This program uses intermittent “quick-look” ECG checks for patients as necessary based on observed signs and symptoms. Four cardiac arrests have occurred during exercise in this program over a period and all patients were successfully resuscitated. Thus, it is clearly that properly supervised CRPs can with little or no use of CTEM. ECG Monitoring in Cardiac Rehabilitation Cardiac rehabilitation should be initiated after hospital in a safe and should include and risk education in the of exercise, and patients with CAD a greater risk of cardiac events than the and some have reported a risk of sudden cardiac death as high as ECG of cardiac patients those as have shown frequent of during at heart rates lower than the from exercise and ST-segment depression are often prevalent during and patients are often at the time of these there is a of graft during the first year coronary artery bypass Because those with CAD a greater risk of having a cardiac event associated with exercise, some have that all patients with CAD are at those who have had These patients typically have shown a high rate of to within the first 6 months or other procedures such as or Given recommendations for CTEM up to 6 months for patients have been because (1) the high rate of within 6 months after (2) the use of by (3) the of (4) the showing significant disease in and and (5) the to the and of the coronary artery during procedures and the increased likelihood of cardiovascular complications can occur as frequently in maintenance participants who have had procedures as in patients who have a and of ECG Monitoring The most currently used for ECG monitoring (1) CTEM by or and (2) intermittent ECG monitoring by either “quick-look” with defibrillator periodic or periodic The purposes of CTEM are (1) as a to potentially cardiac that can be before or other complications (2) that the patient remains within their prescribed target heart rate and (3) provide continuous feedback on heart rate and to the CRP are more to be by CTEM over training sessions than during exercise The pros and cons of CTEM are presented in Table Although 7 to 12 weeks of CTEM has previously been recommended due to the risk of exercise related untoward others that 2 to 4 weeks of CTEM is for most have the position that CTEM should be to moderate to or high-risk patients In the 1995 Exercise position paper, three activity classifications with CTEM recommendations for have been monitoring for apparently healthy individuals is not whereas ECG monitoring for and high-risk cardiac patients is recommended for at least 6 to 12 sessions. The that all patients with CAD should have ECG monitoring and medical supervision for at least 6 to 12 sessions during the early of although the sessions should be For to high-risk patients, CTEM and medical supervision is recommended for 6 to 12 sessions or or the patient safe activity levels and the CRP staff have determined that exercise is and The patient must also be to rate and The has recommended that high-risk patients who have the in Table 4 be supervised and have CTEM. However, there is no on monitoring should be The has presented minimal guidelines for ECG monitoring that intensive monitoring (i. e. , CTEM or intermittent ECG monitoring) when clinically to less intensive monitoring, and patient However, specific risk stratification and duration of monitoring issues are not In the 1995 Practice Guidelines for Cardiac ECG monitoring issues are to an even extent and the is to other position and guidelines for Because cardiovascular complications to the time some have recommended CTEM over many weeks to potentially However, the of this may be to the patient and its may be Most that monitored sessions should include by of by the and for equipment the degree to which should be monitored during CRP sessions has not been It is that monitoring may increase patient on staff and patient To the optimal of ECG monitoring, one must the risk level of the individual to be This is determined by many factors, including the extent of the disease and overall Most will agree that those at greatest risk of cardiovascular complications have multiple risk factors, CAD or myocardial or during exercise, a marked in a low exercise or as moderate to high risk by the AACVPR, 34 ACSM, 35 or require special and should be monitored (1) signs or of health (2) that may of (3) of or that may exercise and (4) physician of myocardial and This that use of CTEM may be for information on some of these telemetered electrocardiographic monitoring may be useful for those who heart rate because of physical or or those who have not previously had a exercise or For these CTEM with of cardiac during daily exercise to the exercise a is a number of studies have to on the optimal duration and degree of ECG monitoring for risk stratified patients. In and reported a rate during the first 7 weeks of Phase II exercise, which decreased to during the 5 of the patients in this had an onset of during the 5 weeks of the program. on these and that cardiac exercise monitoring for patients with events was and recommended a minimum monitoring period of 7 to 12 However, a size was used in this In 1984, and recommended a ECG monitoring period of 4 weeks for patients event based on a low incidence of arrhythmias and complications observed during exercise, provided they had undergone and conducted a retrospective study of patients who had undergone or who had a myocardial infarction and