Is it advisable to add load to an underperforming heart with moderate tricuspid regurgitation until the root causes of low Systemic Vascular Resistance Index (SVI) are addressed?

Exercise in Moderate Tricuspid Regurgitation with Normal Right Ventricular Function

For a patient with moderate tricuspid regurgitation, normal right ventricular function (TAPSE 2.3 cm, S' 12 cm/s), no pulmonary hypertension (RVSP 17 mmHg), and already tolerating 30-45 minutes of daily moderate-paced walking without symptoms, continuing and potentially advancing exercise is appropriate and does not require surgical correction of the TR first. 1

Why Exercise is Safe and Beneficial in This Context

Your patient's hemodynamic profile indicates the TR is not hemodynamically significant despite being moderate in severity. The key protective factors are:

• Normal RV function: TAPSE of 2.3 cm and S' velocity of 12 cm/s are both well above dysfunction thresholds (TAPSE <17 mm, S' <10 cm/s indicate impairment) 1
• No pulmonary hypertension: RVSP of 17 mmHg is completely normal (pulmonary hypertension begins at >40 mmHg) 2
• Absence of right heart failure symptoms: The patient walks 30-45 minutes daily without problems 1

The right ventricle is handling the volume load from moderate TR without decompensation, which is the critical determinant of whether additional exercise load is safe. 3, 4

The Flawed Logic of "Fixing First, Then Exercising"

Your reasoning contains a fundamental misunderstanding of when TR becomes problematic:

Moderate TR with preserved RV function does not meet surgical criteria. 3, 1 Surgery for isolated TR is indicated only when:

• TR is severe (not moderate) with symptoms unresponsive to medical therapy 3, 1
• Progressive RV dilation or systolic dysfunction develops despite medical management 3, 1
• The patient requires left-sided valve surgery (then concomitant TR repair is performed) 3

Operating on moderate TR with normal RV function would expose the patient to surgical risk without established benefit. 1 The 2014 AHA/ACC guidelines give only a Class IIb recommendation (weakest positive recommendation) for tricuspid valve repair in moderate functional TR, and only when performed during left-sided valve surgery with pulmonary hypertension present. 3

Exercise Does Not Harm a Compensated Right Ventricle

The concern about "adding load to an underperforming heart" mischaracterizes the situation:

• The heart is not underperforming—RV function is normal by all measured parameters 1
• Exercise-induced increases in cardiac output are physiologic and do not cause harm when RV function is preserved 3
• The patient's 3-month track record of daily walking without symptoms demonstrates exercise tolerance 1

Exercise testing is actually recommended (Class IIb) for assessing exercise capacity in patients with severe TR and minimal symptoms, precisely because it helps determine functional status. 3 Your patient with moderate TR and proven exercise tolerance has even less concern.

When Would Intervention Become Necessary?

Monitor for these specific changes that would trigger consideration of intervention:

• Progression to severe TR (vena contracta ≥7 mm, EROA ≥0.4 cm², central jet ≥50% of right atrium) 3, 1
• Development of RV dysfunction (TAPSE declining to <17 mm, S' velocity <10 cm/s) 1
• Tricuspid annular dilation progressing to ≥40 mm (or ≥21 mm/m² indexed) 1
• Symptoms of right heart failure (peripheral edema, ascites, hepatomegaly, elevated JVP) unresponsive to diuretics 3, 5
• Development of pulmonary hypertension (RVSP >35-40 mmHg) 1

If the patient required left-sided valve surgery for another reason, concomitant tricuspid annuloplasty would be considered at that time given the moderate TR and any annular dilation. 3, 1

The Danger of Delaying Exercise

Deconditioning from excessive activity restriction can worsen functional capacity and quality of life without providing any cardiac benefit. 3 The traditional teaching that functional TR should be "fixed first" before resuming normal activity applies only to:

• Severe TR with RV dysfunction 3, 1
• Symptomatic patients with right heart failure 3
• Patients with severe irreversible RV dysfunction or pulmonary hypertension (where surgery may be futile) 1

None of these apply to your patient.

Recommended Management Strategy

Continue current exercise regimen and consider gradual advancement based on symptoms:

• Maintain daily 30-45 minute walks at moderate pace 1
• Gradual progression is safe if the patient remains asymptomatic 3
• Medical optimization: Ensure adequate diuretic therapy if any volume overload develops 3, 5
• Serial echocardiographic monitoring every 6-12 months to assess for progression of TR severity, RV size/function, and development of pulmonary hypertension 1

The "root cause" you seek to identify is likely right ventricular and annular remodeling from chronic volume load, but this has not yet caused RV dysfunction or symptoms. 6, 7 Surgical intervention before these complications develop lacks evidence of benefit and exposes the patient to unnecessary risk. 1