How We Ranked These
Every food on this list was scored using KibbleIQ’s ingredient analysis rubric, which evaluates protein quality, filler content, preservative safety, and ingredient transparency on a 0–100 scale. For Mastiffs with heart disease, we weighted Tidholm 1997 (JAVMA) on giant-breed DCM prevalence patterns, Meurs 2007 on cardiac genetic variants, the Wess 2010 Doberman methodology (referenced for staged DCM evaluation), the FDA 2018–2019 dilated cardiomyopathy advisory, Adin 2019 (JAVMA) on diet-associated DCM, the ACVIM 2020 DCM Consensus Statement, the Boswood 2016 EPIC trial methodology, the Summerfield 2012 PROTECT trial, Kaplan 2018 (PLoS One) on taurine-deficiency-responsive diet-DCM cases, the WSAVA Global Nutrition Committee guidelines, and Freeman 2017 on cardiac dietary recommendations.
Our ranking weights AAFCO feeding-trial substantiation per WSAVA Pillar 4 (gold standard for chronic-management feeding), grain-inclusive cardiac-conservative formulation per the FDA advisory, on-staff board-certified veterinary nutritionist availability per WSAVA Pillar 2, recipe stability across batches (cardiac patients tolerate fewer recipe disruptions), and giant-breed-appropriate calorie density and calcium-phosphorus ratios. We did not weight low-sodium formulations as default-preferred — sodium restriction is contraindicated at preclinical stages per the ACVIM 2020 consensus and reserved for Stage C and D congestive heart failure.
Our Top 5 Picks
1. Purina Pro Plan Complete Essentials — B (82/100)
Purina Pro Plan Complete Essentials is our top pick because it delivers AAFCO feeding-trial substantiation (Method 1, gold standard), WSAVA-pillar-complete manufacturing with on-staff board-certified veterinary nutritionists, grain-inclusive formulation aligned with the FDA 2018–2019 cardiac advisory, and consistent recipe stability suitable for chronic cardiac management. The recipe uses real chicken as the first ingredient, whole grain rice and barley as the carbohydrate base, and maintains adequate maintenance sodium for Mastiffs at preclinical stages where sodium restriction is contraindicated.
For Mastiff owners whose veterinary cardiologist recommends a cardiac-conservative grain-inclusive maintenance diet, this is the WSAVA-aligned default. Read our full Purina Pro Plan Complete Essentials review → · Shop on Amazon →
2. Hill’s Science Diet Adult — B (80/100)
Hill’s Science Diet Adult provides AAFCO feeding-trial substantiation, WSAVA Pillar 2 compliance via the largest on-staff veterinary nutrition team in the consumer kibble industry, grain-inclusive whole-grain formulation, and large-breed-appropriate calcium and phosphorus levels meeting the AAFCO Dog Food Nutrient Profiles for adult large-breed maintenance. The recipe avoids legume binders that the FDA 2018–2019 advisory and Adin 2019 temporally associated with diet-associated DCM. Hill’s veterinary nutrition team is the largest in the consumer kibble space, and their cardiac-research depth supports mainstream feeding for cardiac-affected dogs.
For owners whose Mastiff’s cardiologist recommends a maintenance diet that “just stays consistent,” Hill’s Science Diet Adult is a low-variability default. Read our full Hill’s Science Diet review → · Shop on Amazon →
3. Royal Canin Great Dane — B (76/100)
Royal Canin Great Dane is the giant-breed-engineered adult-maintenance option, with kibble shape designed for the giant-breed jaw, calcium-and-phosphorus-controlled formulation appropriate for adult giant-breed maintenance (target Ca 1.0–1.6% DM, P 0.8–1.4% DM, Ca:P 1.1–1.4:1 per the AAFCO Dog Food Nutrient Profiles), L-carnitine fortification supporting myocardial energy metabolism, and adequate maintenance sodium. While Royal Canin does not offer a Mastiff-specific U.S. retail formula, the Great Dane formulation is the closest giant-breed analog and is appropriate substitution feeding for Mastiffs at maintenance stages of cardiac disease.
Manufactured by Mars Petcare with on-staff veterinary nutritionists meeting all 7 WSAVA assessment pillars. Read our full Royal Canin Great Dane review → · Shop on Amazon →
4. Wellness Complete Health — B (84/100)
Wellness Complete Health earns the highest ingredient-rubric score on this list (84/100) thanks to deboned chicken and chicken meal as the top two ingredients, whole grain barley and oatmeal as the carbohydrate base, and no legume binders. The grain-inclusive formulation aligns with FDA-advisory cardiac-conservative feeding. Wellness uses formulation-only AAFCO substantiation rather than feeding trial — one notch below feeding-trial Pro Plan and Science Diet, but still meeting AAFCO Dog Food Nutrient Profiles for adult maintenance.
For owners willing to pay a premium for higher-quality named meats while staying inside the FDA-advisory grain-inclusive frame and tolerating the slightly-less-rigorous AAFCO substantiation. Read our full Wellness Complete Health review → · Shop on Amazon →
5. Royal Canin Adult — B (78/100)
Royal Canin Adult provides another WSAVA-aligned grain-inclusive option from a manufacturer with substantial on-staff veterinary research depth, useful for Mastiff owners whose preference is the standard Royal Canin formulation framework rather than the giant-breed-specific Great Dane line. The base Adult formulation uses chicken by-product meal, brewers rice, corn, and wheat — a grain-inclusive carbohydrate matrix consistent with the WSAVA-aligned cardiac-conservative default.
Wide retail availability and consistent manufacturing tolerances support chronic-management logistics. Read our full Royal Canin review → · Shop on Amazon →
What to Look for in Food for a Mastiff with Heart Disease
Match the food to the ACVIM 2020 disease stage. Per the ACVIM 2020 DCM Consensus Statement, treatment is staged similar to the MMVD framework: Stage A (breed-prevalent risk, no echocardiographic findings) requires no medication or sodium restriction; Stage B1 (subclinical, no echocardiographic remodeling) requires monitoring only; Stage B2 (echo-confirmed remodeling) adds pimobendan per the EPIC trial methodology; Stage C (active CHF) adds furosemide, an ACE inhibitor, and dietary sodium awareness; Stage D (refractory CHF) escalates diuretics and may require formal sodium restriction. Diet stage should match disease stage — over-treating preclinical disease with low-sodium therapeutic kibble adds nothing.
Stay grain-inclusive per the FDA advisory. Per the FDA 2018–2019 dilated cardiomyopathy advisory and Adin 2019 in JAVMA, grain-free formulations heavy in peas, lentils, chickpeas, and potatoes have been temporally associated with diet-associated DCM. Per Kaplan 2018 in PLoS One, a subset of diet-associated DCM cases showed taurine-responsive cardiac improvement on diet change plus taurine supplementation. The FDA case series included Mastiffs and other giant breeds; stacking diet-associated risk on top of inherited risk is hard to justify. Grain-inclusive cardiac-conservative formulations are the current default per WSAVA and ACVIM 2020.
AAFCO feeding-trial substantiation matters more in chronic disease. Per WSAVA Pillar 4, AAFCO Method 1 (feeding trial) tests the actual finished product on dogs over 26 weeks with measurable health-outcome endpoints. AAFCO Method 2 (formulation only) tests that the recipe meets nutrient minimums on paper. For a Mastiff already managing chronic cardiac disease, dietary stability is one less variable to monitor in echocardiographic follow-up. Pro Plan, Science Diet, and Royal Canin all use feeding-trial substantiation; Wellness Complete Health uses formulation only.
Watch for taurine adequacy and consider supplementation under cardiologist direction. Per Kaplan 2018 in PLoS One and Adin 2019, certain Mastiff cardiac cases (and other diet-associated DCM cases) have shown taurine-deficiency-responsive cardiac dysfunction. Standard maintenance kibbles do not require taurine supplementation under AAFCO Dog Food Nutrient Profiles, but cardiologists managing Mastiffs at Stage B2+ may add 1000–2000 mg taurine daily and 1000–2000 mg L-carnitine daily based on plasma taurine and echocardiographic indices. This is a cardiology-directed decision, not an over-the-counter recommendation.
Maintain ideal body condition score 4–5 of 9. Per Saker 2006 and the AAHA 2014 weight management guidelines, obesity exacerbates cardiac workload and reduces preclinical-to-clinical interval in DCM. Calorie restriction to 60–70% of ideal-body-weight maintenance energy requirement is the AAHA-consensus weight-loss protocol. Mastiffs are at elevated obesity risk simply due to their large body mass and the practical difficulty of strict calorie measurement at giant-breed feeding volumes. Bowl-portioned twice-daily feeding with a calorie-counted approach using a kitchen scale (gram-precise) is the operational substrate. Avoid free-feeding in any cardiac-affected Mastiff.
Coordinate diet changes with cardiac monitoring. Per the ACVIM 2020 DCM Consensus, Mastiffs at Stage B2+ are monitored with echocardiography (left ventricular internal diameter in diastole, fractional shortening, vertebral heart score) at 6–12 month intervals. Significant diet changes (sodium content shift, protein source change, calorie density change) can transiently shift body weight and fluid status. Time diet transitions to occur at least 4 weeks before scheduled cardiac recheck, and inform your cardiologist if a recent diet change might be confounding monitoring values. This is a coordination concern, not a contraindication.
Bottom Line
Mastiffs and giant-breed dogs carry elevated dilated cardiomyopathy (DCM) and giant-breed cardiomyopathy risk per Tidholm 1997 and Meurs 2007. Primary therapy is staged per the ACVIM 2020 DCM Consensus — pimobendan at Stage B2 per the EPIC trial methodology, furosemide and ACE inhibitor at Stage C, sodium restriction only at Stage C–D. Per the FDA 2018–2019 advisory, grain-free legume-heavy formulations have been temporally associated with diet-associated DCM — grain-inclusive cardiac-conservative is current consensus. Our top pick is Purina Pro Plan Complete Essentials for cardiac-conservative grain-inclusive maintenance. Hill’s Science Diet Adult is the AAFCO feeding-trial WSAVA-aligned default. Royal Canin Great Dane is the giant-breed-engineered analog. Wellness Complete Health is the premium named-meats option. Royal Canin Adult is the WSAVA-aligned mainstream choice. See also our general dog heart disease guide. Match diet stage to disease stage per ACVIM 2020, stay grain-inclusive per the FDA advisory, choose AAFCO feeding-trial substantiation per WSAVA Pillar 4, maintain ideal BCS 4–5 of 9 per AAHA 2014, and coordinate diet changes with echocardiographic monitoring schedules.
See more: Browse our full Best Dog Food by Condition: 2026 Cluster Index — breed-condition guides organized into clinical clusters (cardiac, oncologic, dermatologic, gastrointestinal, orthopedic, endocrine, metabolic, dental, athletic) anchored on peer-reviewed primary literature.