11.3 Cardiac Rehabilitation Phases and Exercise Monitoring

Cardiac Rehabilitation Phases and Exercise Monitoring

Cardiac rehabilitation combines exercise, education, psychosocial support and management of cardiovascular risk. Eligible patients include people recovering from myocardial infarction (MI), coronary revascularization or valve surgery, and people with stable heart failure. The team assesses functional capacity, agrees on goals with the patient and adjusts supervision as medical status and independence change.

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Cardiac Rehabilitation in the Saudi MOH Model

The Saudi MOH 2025 guideline describes three phases. In four-phase programs, what some services call Phase IV corresponds to long-term community maintenance. Check the local phase definition before inferring the setting or degree of supervision.

I. Inpatient acute care
    │  Medical stability, safe mobility, discharge education and referral
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II. Structured outpatient rehabilitation
    │  Exercise assessment, individualized training and risk-factor support
    ▼
III. Long-term maintenance
       Home or community activity, self-management and follow-up

Phase I: Inpatient Recovery

Begin after the physician confirms stability. Review the event or procedure, recent symptoms, rhythm, blood pressure and wound status. Start with a tolerated task such as sitting out of bed, standing or short supervised walking. Check symptoms and hemodynamic response before advancing distance, repetitions or stairs. Telemetry and observation follow the patient's condition and inpatient protocol. Teach warning signs, activity progression and the outpatient referral plan before discharge.

After median sternotomy, check the surgical team's precautions and inspect the wound. New clicking, instability, drainage or unexpected sternal pain warrants assessment. If the surgical team uses the Keep Your Move in the Tube strategy, the patient keeps the upper arms close to the trunk for supported transfers and other loaded tasks to shorten the lever arms. Practice the actual transfer at a tolerable load and monitor the response.

Phase II: Structured Outpatient Rehabilitation

Review the referral, stability and medications. Evaluate function, rhythm, ischemic symptoms, blood pressure response and risk factors. Use available exercise testing to help set a starting workload and monitoring needs. Unstable angina, decompensated heart failure and uncontrolled arrhythmia call for medical review before training.

• Aerobic training: The Saudi MOH outpatient conditioning example uses moderate work for 20–40 minutes at least two to three times weekly, with a warm-up and cool-down. Borg 6–20 RPE of 11–14 is one guide. Adapt mode, duration and work rate to the baseline test, symptoms, blood pressure and prescribed limits.
• Intensity and progression: Use measured responses when available. Rate-limiting medication or atrial fibrillation can complicate heart-rate targets, so include perceived exertion and the observed workload response. If testing identifies a reproducible ischemic or angina threshold, the prescribing team can set a lower training limit. Increase one component at a time as the patient tolerates it.
• Resistance training: Begin with tolerated loads and controlled breathing, progressing with clinical stability. The Saudi MOH post-open-heart pathway calls for a healed wound and physician clearance, and recommends starting its formal resistance program after six weeks following sternotomy. Trials of earlier supervised recovery in selected patients used individualized exercises and progression. Use the applicable surgical and rehabilitation plan.
• Secondary prevention: Address activity habits, medication adherence, nutrition, tobacco use, and mental health as part of the program.

Phase III: Long-Term Maintenance

Following outpatient rehabilitation, medically stable patients who can exercise safely and independently transition to a long-term plan. Base home or community activities on functional assessment and individual goals. Review warning signs, risk-factor management and follow-up. A change in symptoms or stability calls for reassessment.

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Risk and Monitoring in Outpatient Rehabilitation

The Saudi MOH guideline combines exercise-test findings, symptoms, cardiac function and history. Its resting left ventricular ejection fraction (LVEF) bands are examples of how one result contributes to the risk profile.

A patient with LVEF 38% and exercise-induced nonsustained ventricular tachycardia has high-risk findings. Conversely, LVEF 55% can occur with significant ischemia or arrhythmia. Review the whole profile and plan supervision and ECG monitoring with the team. Risk grouping guides monitoring after stabilization. Acute instability requires assessment before training.

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Telemetry Monitoring and Electrocardiographic Ischemia

Telemetry can reveal a rhythm or ST change during monitored exercise. Check the trace quality, symptoms and vital signs. New chest pressure with an ischemic-appearing change warrants stopping the training session and following the facility response.

ST changes during diagnostic exercise testing

Horizontal or downsloping ST depression of at least 1 mm, assessed 60–80 ms after the J point, can support ischemia in an interpretable ECG. It is one finding to interpret with the baseline and other clinical evidence. The threshold for identifying a concerning ECG change and the criteria for stopping a diagnostic test serve different purposes. The AHA stopping criteria are summarized below.

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Arrhythmias During Exercise

A premature ventricular contraction (PVC) typically appears as an early wide QRS with ventricular morphology. PVCs of similar shape are called unifocal. A change in morphology, an increasing burden or a run can matter, especially with exertional symptoms or abnormal blood pressure. Two consecutive PVCs form a couplet. Ventricular bigeminy alternates a conducted beat with a PVC. Inspect the tracing and check the patient to distinguish a rhythm change from artifact.

Nonsustained ventricular tachycardia (NSVT) is a ventricular run of at least three beats at a tachycardic rate that terminates spontaneously before 30 seconds. A short wide-complex run on exercise telemetry can raise suspicion for NSVT. Associated dizziness, hypotension, chest pain or signs of poor perfusion call for stopping and urgent assessment. Sustained VT or an arrhythmia that compromises output is an absolute stopping indication in the AHA diagnostic testing table.

Atrial fibrillation commonly has irregular R–R intervals and no discrete repeating P waves. Loss of coordinated atrial contraction, irregular ventricular filling intervals and ventricular rate can affect cardiac output. For a stable patient with controlled AF and clearance, choose workload using symptoms, perceived exertion and measured response. A new rapid or poorly tolerated rhythm calls for stopping, evaluating symptoms and perfusion, and following the service response. Rate targets depend on the clinical context.

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Hemodynamic Monitoring and Diagnostic Exercise Test Termination

During graded dynamic work, systolic pressure usually rises, while diastolic pressure changes less. Interpret the trend using the workload, measurement conditions, symptoms and ECG. Diagnostic tests and rehabilitation training have distinct protocols.

Relative findings call for clinical judgment under the testing protocol. The Saudi MOH cardiac rehabilitation CPET protocol lists an SBP fall greater than 10 mmHg with increasing work and onset of angina among its absolute stop criteria. For training, use the program's limits. Stop and escalate promptly for new angina-like symptoms, poor perfusion or concerning telemetry.

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Clinical Case Scenario: Outpatient Phase II Progression

A 62-year-old male 4 weeks post-CABG $\times 3$ vessels attends his 6th Phase II cardiac rehabilitation session. His resting vitals are BP $122/78\ \text{mmHg}$, HR $68\ \text{bpm}$ (on carvedilol), room air $SpO_2\ 97\%$. Resting telemetry confirms normal sinus rhythm. Sternal incision is intact without erythema or click.

During treadmill walking at $2.8\ \text{mph}$ and $3\%$ grade (about 4.3 METs by the walking equation):

• Telemetry shows normal sinus rhythm at $94\ \text{bpm}$ (within his calculated target HR zone of $88\text{--}98\ \text{bpm}$).
• He rates his exertion as 12 on the Borg 6-20 scale.
• At minute 14, telemetry reveals three consecutive wide, bizarre QRS complexes at a rate of $135\ \text{bpm}$ without preceding P-waves, followed by a brief return to sinus rhythm with frequent unifocal PVCs.
• The patient reports sudden onset of lightheadedness, and his blood pressure drops from $142/82\ \text{mmHg}$ to $108/70\ \text{mmHg}$.

Therapist action: Stop the treadmill and assist the patient to a safe position. New lightheadedness with a 34 mmHg systolic fall and a short wide-complex run calls for urgent assessment. Activate the facility response, assess vital signs and perfusion, and monitor the rhythm. The team evaluates the tracing and obtains a diagnostic ECG as appropriate. Resume only after evaluation and clearance.