Background <p>Peripartum cardiomyopathy (PPCM) is a life-threatening form of heart failure characterized by substantial heterogeneity in left ventricular recovery. Identifying reliable and readily accessible biomarkers associated with myocardial recovery remains an important clinical challenge. Although systemic inflammatory indices such as the systemic immune-inflammation index (SII) have been associated with persistent left ventricular dysfunction in PPCM, they do not incorporate nutritional and immune-related parameters that may also influence clinical outcomes. The Naples Prognostic Score (NAPLES), which integrates inflammatory, immune, and nutritional parameters, has emerged as a promising prognostic index in cardiovascular disease; however, its role in PPCM has not yet been elucidated. In this context, this study aimed to investigate the association between the Naples Prognostic Score and left ventricular functional recovery in patients with peripartum cardiomyopathy, and to compare its discriminatory ability with that of the Systemic Immune-Inflammation Index (SII).</p> Methods <p>This retrospective single-center study included 30 patients diagnosed with PPCM between 2015 and 2025. Left ventricular functional recovery was defined as an LVEF ≥ 50% at the last available follow-up assessment, provided that follow-up duration was at least 12 months. Laboratory parameters obtained on the day of hospital admission (baseline) were used to calculate NAPLES and SII. Patients were categorized according to the presence or absence of left ventricular functional recovery. Receiver operating characteristic (ROC) curve analysis and risk stratification based on optimal cut-off values were performed.</p> Results <p>Sixteen patients (53.3%) achieved left ventricular functional recovery, whereas 14 (46.7%) did not. Patients without left ventricular functional recovery exhibited significantly higher SII values and higher NAPLES scores. SII demonstrated good discriminatory ability for differentiating patients according to left ventricular recovery status (AUC = 0.800), and NAPLES also showed a significant association with left ventricular recovery status (AUC = 0.731). A combined model incorporating both SII and NAPLES yielded the highest numerical AUC (0.818), although no statistically significant improvement compared with SII alone was observed. An SII &gt; 1332 and a NAPLES score ≥ 3 were associated with a significantly increased risk of persistent left ventricular dysfunction.</p> Conclusions <p>Both SII and NAPLES were significantly associated with left ventricular functional recovery in patients with peripartum cardiomyopathy. By integrating inflammatory, nutritional, and immune-related parameters, the Naples Prognostic Score may provide complementary biological and clinical information beyond conventional inflammatory indices. These findings suggest that readily available biomarkers such as SII and NAPLES may provide additional clinical information and warrant further investigation in PPCM. However, larger prospective studies are required before their clinical applicability can be established.</p>