How Doctors Diagnose a Spongy Heart

When you look at an imaging report for Left Ventricular Noncompaction (LVNC), you will often see various measurements and “ratios.” It is important to understand that these numbers are used to describe the look of your heart muscle, but they are not always enough to diagnose a disease on their own ^[1]. Doctors use specific sets of “rules” called imaging criteria to evaluate if your heart qualifies as “noncompacted.” There is no universally accepted gold-standard criterion, and an experienced doctor will interpret these numbers alongside your symptoms and overall heart function.

Two Common Imaging Criteria: Jenni and Petersen

Because the heart looks different depending on whether it is being viewed with ultrasound or MRI, there are different sets of criteria used:

• The Jenni Criteria (Echocardiogram): This is commonly used for ultrasound. A doctor looks at the “spongy” (noncompacted) layer and the solid (compacted) layer at the end of a heartbeat, when the heart is most contracted ^[2]. If the spongy layer is more than twice as thick as the solid layer (a ratio of >2.0), along with deep recesses with blood flow, it meets the Jenni criteria ^[3].
• The Petersen Criteria (Cardiac MRI): MRI provides a much more detailed picture. For this test, the layers are measured when the heart is relaxed and filled with blood ^[4]. Because the muscle is more stretched out during this phase, the threshold is slightly higher: the spongy layer must be more than 2.3 times the thickness of the solid layer to meet the Petersen criteria ^[5].

Why Healthy Hearts Can Meet These Criteria

One of the biggest challenges with these criteria is that they can be “too sensitive.” This means they often “overcall” the condition, identifying hypertrabeculation in healthy people who don’t actually have a heart disease ^[6][7].

Your heart is a dynamic organ that changes shape based on the work it has to do. Certain situations can cause a healthy heart to develop more “mesh-like” muscle bundles:

• Athletes: People who do intense endurance training often develop larger, more trabeculated hearts as a normal response to exercise ^[8]. In some specific athletic cohorts, a significant percentage may meet the imaging criteria without having any actual heart problem ^[9]. However, athletes should never assume a finding is benign without a full clinical review.
• Pregnancy: During pregnancy, the amount of blood the heart has to pump increases significantly. This extra load can cause the heart muscle to temporarily appear more noncompacted ^[10]. While it often returns to normal after delivery, pregnancy can also unmask true cardiomyopathy, so careful follow-up is necessary ^[1].
• Ancestry: Research in specific cohorts suggests that individuals of certain ancestries, including those of African descent, may naturally have more prominent heart muscle bundles. However, ancestry is never a substitute for thorough individual assessment ^[11].

Late Gadolinium Enhancement (LGE): A Vital Risk Marker

If you have a cardiac MRI, your doctor may use a special contrast dye called gadolinium to look for Late Gadolinium Enhancement (LGE). This looks for fibrosis—which is essentially microscopic scarring in the heart muscle ^[4].

LGE is not a required diagnostic criterion to say you have LVNC, but it is an incredibly important marker for risk stratification ^[12]. Research has shown that:

1. Higher Risk: Patients with significant LGE have a higher risk of heart rhythm problems (arrhythmias) and heart failure, even if their heart’s pumping function (ejection fraction) is still normal ^[13][14].
2. Scarring vs. Appearance: In studies, the simple ratio of “sponginess” did not reliably predict who would have health issues ^[15]. However, the presence and pattern of LGE-related scarring was strongly associated with future heart health ^[16][12].

If your MRI shows no LGE and you have normal pumping function, this lowers the concern, but it does not completely guarantee safety or prove your heart is just a normal variant. Diagnosis is a “puzzle” where the imaging ratio is just one piece; your symptoms, family history, and the presence of scarring are integrated by your specialist to determine your actual long-term risk ^[17][13].