# US 7,608,418 B2 · NT-proANP and NT-proBNP for diagnosing cardiac diseases > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,608,418 B2 - Document ID: US7608418B2 - Status: Granted - Kind: B2 - Application number: 11/945,309 - Filed: 2007-11-27 - Published: 2009-02-12 - Granted: 2009-10-27 - Earliest claimed: 2005-06-07 - Assignees: Roche Diagnostics Operations, Inc. - Inventors: Georg Hess; Andrea Horsch - Web page: https://patentgrep.com/patent/US7608418B2 ## CPC - G01N 33/6887: {from muscle, cartilage or connective tissue} - G01N 33/6893: {related to diseases not provided for elsewhere} - G01N 2333/58: Atrial natriuretic factor complex; Atriopeptin; Atrial natriuretic peptide [ANP]; Brain natriuretic peptide [BNP, proBNP]; Cardionatrin; Cardiodilatin - G01N 2800/32: Cardiovascular disorders - G01N 2800/325: Heart failure or cardiac arrest, e.g. cardiomyopathy, congestive heart failure - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) ## Abstract Described are methods for diagnosing a cardiac disease, particularly an acute cardiac event, in a patient presenting with symptoms of acute cardiac decompensation, comprising the steps of (a) measuring, typically in vitro, the level of NT-proBNP (N-terminal brain natriuretic peptide) or a variant thereof in a sample from the patient, (b) measuring, typically in vitro, the level of NIT-proANP (N-terminal atrial natriuretic peptide) or a variant thereof in a sample from the patient, (c) combining the information of the measured levels of NT-proANP and NT-proBNP, wherein an increased level of NT-proANP in presence of a non-increased or weakly increased level of NT-proBNP indicates the presence of an acute cardiac event, or wherein an increased level of NT-proANP in presence of a highly increased level of NT-proBNP indicates the presence of a chronic cardiac disease. The methods also allow distinguishing an acute cardiac event from decompensation of a chronic cardiac disease. Described also are corresponding kits and to methods of treatment of cardiac diseases. ## Claims ### Claim 1 A method for distinguishing an acute cardiac event from a chronic cardiac disease in a patient presenting with symptoms of acute cardiac decompensation, the method comprising the steps of measuring in a sample from the patient, within 24 hours after occurrence of the symptoms, a level of NT-proANP or an isoform thereof having at least 80% sequence similarity, measuring in a sample from the patient, within 24 hours after occurrence of the symptoms, a level of NT-proBNP or an isoform thereof having at least 80% sequence similarity, and comparing the measured level of NT-proANP with the measured level of NT-proBNP as a means of distinguishing an acute cardiac event from a chronic cardiac disease, wherein a level of NT-proANP of more than 3000 pg/ml and a level of NT-proBNP of less than 1000 pg/ml indicates the presence of an acute cardiac event, and wherein a level of NT-proANP of more than 3000 pg/ml and a level of NT-proBNP of more than 3000 pg/ml and indicates the presence of a chronic cardiac disease. ### Claim 2 (depends on 1) The method according to claim 1 wherein measurements of NT-proANP and NT-proBNP are performed in parallel. ### Claim 3 (depends on 1) The method according to claim 1 wherein the sample is selected from the group consisting of blood, plasma, and serum. ### Claim 4 (depends on 1) The method according to claim 1 further comprising the step of measuring a level of NT-proANP in at least one additional sample. ### Claim 5 (depends on 1) The method according to claim 1 further comprising the step of measuring a level of NT-proBNP in at least one additional sample. ### Claim 6 (depends on 1) The method according to claim 1 wherein a time-course of NT-proANP and/or NT-proBNP is established. ### Claim 7 (depends on 1) The method according to claim 1 further comprising the step of expressing the measured levels of NT-proANP and NT-proBNP as a ratio. ### Claim 8 (depends on 1) The method according to claim 1 further comprising the step of measuring in a sample from the patient at least one biomarker selected from the group consisting of troponin T, creatine kinase (CK), creatine kinase muscle-brain (CK-MB), and myoglobin. ### Claim 9 (depends on 1) The method according to claim 1 further comprising the step of measuring a diagnostic indicator selected from the group consisting of left ventricular ejection fraction, echocardiogram, angina pectoris, electrocardiogram, parameters of thyroid or kidney function, arterial hypertension, thallium scintigram, angiography, and cardiac catheterization. ### Claim 10 A method for recommending initiation of treatment of a patient for a cardiac disease, wherein the patient presents with symptoms of acute cardiac decompensation, the method comprising the steps of measuring in a sample from the patient, within 24 hours after occurrence of the symptoms, a level of NT-proANP or an isoform thereof having at least 80% sequence similarity, measuring in a sample from the patient, within 24 hours after occurrence of the symptoms, a level of NT-proBNP or an isoform thereof having at least 80% sequence similarity, comparing the measured level of NT-proANP with the measured level of NT-proBNP as a means of distinguishing an acute cardiac event from a chronic cardiac disease, wherein a level of NT-proANP of more than 3000 pg/ml and a level of NT-proBNP of less than 1000 pg/ml indicates the presence of an acute cardiac event, and wherein a level of NT-proANP of more than 3000 pg/ml and a level of NT-proBNP of more than 3000 pg/ml and indicates the presence of a chronic cardiac disease, optionally initiating an examination of the patient by a cardiologist, and recommending the initiation of treatment if the comparison step indicates the presence of a cardiac disease.