What Is RV Strain? Normal Values and How It Is Measured

Right ventricular strain, usually called RV strain, is a measure of how much the muscle of the heart’s right ventricle shortens during each heartbeat, expressed as a negative percentage. A healthy person’s RV free wall strain typically falls around −27%, and values closer to zero indicate the muscle is contracting less forcefully. Over the past decade, RV strain has moved from a research curiosity to a clinical workhorse, helping cardiologists spot early dysfunction in the right side of the heart well before traditional measurements raise an alarm. Its applications stretch from pulmonary embolism and heart failure to cancer treatment monitoring, and the measurement is increasingly available on standard echocardiography machines.

What RV Strain Actually Measures

The right ventricle wraps around the front of the heart in a crescent shape. Unlike the thick-walled left ventricle, which squeezes inward from all directions, the RV contracts primarily by pulling downward, like a bellows shortening from top to bottom. RV strain quantifies that longitudinal shortening. A strain of −25% means the tracked muscle segment shortened by 25% of its original length during systole. More negative values mean stronger contraction; values drifting toward zero mean weaker contraction.

In a normal heart, the RV free wall shortens more vigorously than the interventricular septum. One study of healthy subjects measured free wall peak strain at about −29% compared with roughly −20% for the septum.¹ This difference matters because the septum is shared between both ventricles, so its motion reflects contributions from the left side as well. For that reason, most clinical cutoffs focus on either the RV free wall strain alone or a global longitudinal strain that averages across all visible segments.

The right ventricle’s wall is thinner and more compliant than the left ventricle’s, and the two chambers face very different pressure loads. The pulmonary circulation is a low-pressure system, so the RV normally does far less pressure work. Animal research confirms that the stiffness profiles of the two ventricles differ along different axes, reflecting their distinct filling and ejection patterns.² When pulmonary pressures rise or the RV is damaged, strain is often the first number to deteriorate, sometimes years before ejection fraction changes.

Normal Reference Values

The most commonly reported number is RV free wall longitudinal strain. A large meta-analysis pooling data from dozens of studies in healthy people found the average to be about −27%, with the lower limit of normal around −18%.³ A separate meta-analysis reported a similar weighted mean of about −27% across both tissue Doppler and speckle-tracking methods.⁴

RV global longitudinal strain, which includes the septum’s contribution, runs slightly less negative, with a pooled mean around −23% and a lower limit of normal near −16%.⁵ These numbers provide a useful benchmark, but keep in mind that age, body size, and even which software package your hospital uses can shift the result by a few percentage points. Global strain values are more reproducible across different machine vendors than segment-by-segment measurements.⁶

How RV Strain Is Measured

The most widely used technique is speckle-tracking echocardiography, or STE, performed from a standard ultrasound view focused on the right heart. The software tracks tiny acoustic speckles within the heart muscle frame by frame, computing how far each region moves and how much it deforms. This can be done on a regular echocardiogram without any extra hardware; it just requires the right software and a sonographer who captures a good-quality image.

Cardiac MRI offers an alternative through a technique called feature tracking, which applies a similar concept to MRI cine images. Head-to-head comparisons show a strong correlation between the two approaches for detecting RV dysfunction, with both performing well in distinguishing normal from impaired right ventricles.⁷ That said, agreement is moderate rather than perfect, particularly for regional segments, so a strain value from an echocardiogram is not directly interchangeable with one from MRI without knowing the expected offset.⁸

Pulmonary Embolism

When a blood clot lodges in the pulmonary arteries, the right ventricle suddenly faces a sharp rise in the pressure it has to pump against. RV strain can quantify how much the right ventricle is struggling and, critically, predict whether the patient is likely to survive the next 30 days. In a study of patients with intermediate-risk pulmonary embolism, those who died within a month had meaningfully worse RV global longitudinal strain than survivors. Using a cutoff around −17.7%, the combination of reduced strain with an enlarged RV predicted 30-day mortality near 46%, while patients with better strain and a normal-sized RV had a mortality of only about 1%.⁹

An external validation study in a separate group of patients confirmed these findings, showing that strain below that same cutoff identified patients at higher risk of dying within 30 days, with an area under the curve of about 0.80 for discrimination.¹⁰ Clinicians also look at regional strain patterns. When only certain segments of the RV are affected, a classic pattern emerges where the mid-wall contracts reasonably well but the apex is markedly impaired, mirroring the so-called McConnell sign seen on standard echo. Strain makes this regional dysfunction quantifiable rather than subjective.¹¹

Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a chronic condition where the blood vessels in the lungs progressively narrow, forcing the right ventricle to work harder over months and years. Eventually the RV can fail, and how well it copes with that pressure overload is the single biggest driver of survival. RV free wall strain worse than about −12.5% identified patients with advanced disease, greater RV dysfunction, and a substantially higher rate of death, with an unadjusted hazard ratio above 6 at one year. For every 5-percentage-point decline in strain, the risk of dying roughly tripled after adjusting for age, sex, and disease cause.¹²

Researchers have pushed the concept further by indexing RV strain to the pulmonary artery pressure, creating a ratio that captures how well the right ventricle is adapting to its afterload. This ratio outperformed traditional measures in predicting death or transplant, with high sensitivity and specificity at a defined cutoff.¹³ The same ratio appears to respond to treatment. When PAH-targeted therapies lower pulmonary pressures, the strain-to-pressure ratio improves, and the size of that improvement tracks with long-term outcomes.¹⁴

Heart Failure

The right ventricle often gets overlooked in heart failure, where most attention focuses on the left side. Yet right ventricular dysfunction in heart failure dramatically worsens the outlook for patients. In heart failure with preserved ejection fraction (HFpEF), roughly one in five patients had impaired RV strain (worse than about −17.5%), and that impairment added significant prognostic value for predicting hospitalization and death, even after accounting for other known risk factors. Older conventional measures such as fractional area change did not carry the same independent predictive power.¹⁵

In patients with left-sided heart disease after a heart attack, RV strain also detects subtle dysfunction that traditional echocardiographic measures miss. One study found that RV free wall strain correlated with symptom severity and left ventricular function, and was able to pick up abnormalities that standard indices could not.¹⁶ The implication is straightforward: if you are managing heart failure and ignoring RV strain, you may be missing patients who are deteriorating silently on the right side.

When Advanced Heart Failure Needs a Pump

Patients with end-stage heart failure sometimes receive a left ventricular assist device (LVAD), a mechanical pump that takes over much of the left ventricle’s work. A feared complication is right heart failure after implantation, because the LVAD only assists the left side. Pre-operative RV strain helps predict who is at risk. In one study, a pre-implant RV free wall strain worse than about −5.6% predicted post-operative right heart failure, and the finding held up after adjusting for other risk factors.¹⁷ These measurements can guide surgical planning, helping teams decide whether to implant a temporary right-sided assist device alongside the LVAD.¹⁸

Arrhythmogenic Right Ventricular Cardiomyopathy

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a genetic condition in which the heart muscle, especially on the right side, is gradually replaced by fat and scar tissue. It can cause dangerous arrhythmias and is a recognized cause of sudden cardiac death in young athletes. Diagnosing ARVC is notoriously tricky because the standard criteria rely on a combination of imaging, electrical, and family history features. RV strain has emerged as a particularly sensitive tool here. In a multicenter registry, abnormal RV free wall strain identified over 80% of patients who met the overall diagnostic criteria but whose conventional echo findings alone would have been called normal.¹⁹

MRI-derived RV strain tells a similar story. Patients with definite ARVC had significantly reduced strain in all directions compared with borderline or possible cases, and global longitudinal strain independently predicted disease status.²⁰ For someone undergoing screening because a family member has ARVC, strain can flag early disease before the heart visibly changes shape on a standard scan.

Cardiac Amyloidosis

Amyloidosis deposits abnormal protein fibrils throughout the heart muscle, stiffening it and eventually weakening contraction. Much of the clinical literature has focused on how amyloid affects the left ventricle, where a distinctive “apical sparing” strain pattern has become almost a signature of the disease. The right ventricle shows the same phenomenon. In transthyretin amyloidosis, researchers found a gradient with the best strain values preserved at the RV apex and progressively worse values toward the base.²¹ A separate study looking at both types of cardiac amyloidosis confirmed apical sparing on the right side as well, with the pattern being especially prominent in the AL (light-chain) form.²² Recognizing right-sided involvement matters because it usually signals more advanced disease and a greater burden of amyloid infiltration throughout the heart.

COVID-19 and Critical Illness

During the COVID-19 pandemic, intensivists quickly noticed that severe lung disease placed enormous stress on the right ventricle. Interestingly, the pattern of RV dysfunction in critically ill COVID-19 patients was unusual. A study of patients with severe acute respiratory distress syndrome found that RV dysfunction was much more commonly detected by measures of radial or area-based contraction than by longitudinal strain or standard annular motion. The RV free wall strain was abnormal in about a third of patients, while radial-type measures flagged dysfunction in over 70%.²³ This tells us that COVID-related RV impairment primarily involves the radial component, sparing the usual longitudinal shortening to a surprising degree.

That said, when RV global longitudinal strain was impaired in COVID-19 patients, it carried real prognostic weight. In a study of over 160 patients, worsened RV strain was independently associated with developing ARDS, adding useful risk-stratification information on top of other clinical variables.²⁴ The broader lesson applies beyond COVID-19: in any critically ill patient with acute lung disease, checking RV strain can reveal cardiac compromise that might otherwise be missed until the patient decompensates.

Athletes and the Exercise-Adapted Right Ventricle

Endurance athletes develop a larger, more compliant right ventricle as part of normal cardiac adaptation to training. This is generally harmless and reversible. But teasing apart a healthy “athlete’s heart” from early disease can be difficult, especially when screening for conditions like ARVC in competitive sports. RV strain adds a useful piece of that puzzle.

A meta-analysis of studies comparing RV function before and after endurance exercise found a consistent acute reduction in RV global longitudinal strain after prolonged exertion.²⁵ In most athletes this recovers fully, but in a subset of heavily trained endurance athletes, RV changes may not completely reverse after detraining, raising the question of whether chronic overload can cause lasting damage.²⁶ Higher training intensity has been linked to larger RV volumes and lower ejection fractions on cardiac MRI, a pattern that sits right at the boundary between adaptation and early dysfunction.²⁷ This is exactly the gray zone where serial strain measurements can help, by establishing an individual athlete’s baseline and flagging any decline that goes beyond expected variation.

RV Strain During and After Cardiac Surgery

Cardiac surgery reliably reduces RV function, and strain has been instrumental in quantifying this. Opening the pericardium alone does not seem to do much. Multiple studies show no significant change in RV strain or other measures after the pericardium is incised.²⁸ The real drop comes after cardiopulmonary bypass and especially after the chest is closed. In one study, RV strain went from about −22% at baseline to roughly −16% after bypass, and it stayed near that level after sternal closure.²⁹

Detailed intraoperative analysis paints a finer picture. Longitudinal strain of the RV free wall dropped by about 23% after sternal closure compared to baseline, with the outflow tract segment hit hardest, losing over 40% of its baseline shortening. At the same time, circumferential contraction actually increased slightly, as though the RV was compensating by squeezing in a different direction.³⁰ This phenomenon is well recognized by cardiac anesthesiologists and typically resolves over weeks, but in patients whose RV was marginal before surgery, knowing the expected hit to function guides decisions about vasoactive medications and the timing of extubation.

Cancer Therapy Monitoring

Anthracycline chemotherapy and other cancer treatments can damage the heart, a problem collectively called cardiotoxicity. Monitoring for this has traditionally focused on left ventricular ejection fraction, but that measure drops late, often after irreversible damage has occurred. RV free wall strain may catch right-sided cardiotoxicity even earlier. In a study of breast cancer patients receiving anthracyclines, changes in RV free wall strain did not correlate with changes in standard measures such as left ventricular ejection fraction or tricuspid annular motion, suggesting it captures a different and potentially earlier signal of RV damage.³¹ The evidence base for adding RV strain to routine cancer cardiology protocols is still growing, but the logic parallels what happened with left ventricular strain a decade ago: an earlier signal means earlier intervention.

Fetal and Pediatric Considerations

RV strain is not a static value across a lifetime. During fetal development, the magnitudes of RV global and free wall strain actually decrease as the baby grows, reflecting changes in myocardial composition and loading conditions in the womb. After birth, the pattern reverses: strain magnitudes increase through the first year of life. Throughout this entire arc from mid-gestation through infancy, the RV maintains a characteristic base-to-apex gradient, with the basal segments showing the highest strain and the apex the lowest.³² Pediatric cardiologists use age-specific norms rather than adult cutoffs, and intervendor agreement for RV strain is better at certain frame rates and heart rates. In children with higher heart rates (above 100 beats per minute), agreement between software platforms drops, especially when image data are compressed.³³

For congenital heart disease, RV strain is particularly valuable in patients who have undergone repair of tetralogy of Fallot, a condition where the right ventricle endures lifelong volume overload from a leaky pulmonary valve. In these patients, RV strain declined over follow-up even while ejection fraction stayed stable, making it a more sensitive early warning sign of RV deterioration.³⁴

Technical Pitfalls Worth Knowing About

RV strain is sensitive and clinically useful, but it is not yet as standardized as left ventricular strain. Several practical issues affect the numbers you get. Global measures (averaging across the whole RV free wall or all visible segments) are reasonably reproducible across different ultrasound machines. Segment-by-segment values, however, vary by as much as 25 to 35% depending on the vendor, compared with only 10 to 15% variability for global strain.³⁵ For this reason, expert consensus recommends against using segmental RV strain in clinical decision-making, where variability on the order of 30 to 40% makes individual segment values unreliable.³⁶

Image quality matters a great deal. The RV free wall sits just behind the sternum, where ultrasound penetration can be poor. If the tracking software loses the wall for even a few frames, the strain curve becomes unreliable. Serial comparisons, such as monitoring a patient over months of chemotherapy or following someone with PAH, should ideally be done on the same machine with the same software, because switching platforms introduces noise that can mimic a real change in function. When comparing echocardiographic strain with MRI-derived values, expect systematic differences: the two modalities correlate well for identifying dysfunction but do not produce interchangeable absolute numbers.³⁷

Tracking Treatment Response

One of the most promising frontiers for RV strain is using it to gauge whether a therapy is working. In PAH, for example, starting pulmonary vasodilator medications aims to lower the pressure the RV pumps against. A case report following a patient with idiopathic PAH showed that after six months on combination vasodilator therapy, RV free wall strain improved from a markedly abnormal level back to about −27%, paralleling improvements in symptoms and other echo findings. Alongside the strain value itself, the shape of the post-systolic strain curve changed from a pattern associated with severe dysfunction to a more benign one.³⁸ This kind of individual-level treatment tracking has the potential to make clinic visits more informative: instead of simply asking patients how they feel, clinicians can watch whether the right ventricle is objectively recovering or continuing to struggle.