[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Clinical exam](https://durgical.com/en/clinical-exam/) › [Cardiovascular system](https://durgical.com/en/clinical-exam/#a-cardiovascular) › Abnormal pulses: paradoxus, alternans, parvus et tardus, bounding [Clinical exam](https://durgical.com/en/clinical-exam/) · [Cardiovascular system](https://durgical.com/en/clinical-exam/#a-cardiovascular) # Abnormal pulses: paradoxus, alternans, parvus et tardus, bounding - Sign The shape of the pulse, not just its rate, gives away heart problems: a pulse that weakens on inspiration, alternates or arrives late. Updated 2026-11-01 **See it in 3D:** [Radial artery](https://durgical.com/en/anatomy/radial-artery/) · [Common carotid artery](https://durgical.com/en/anatomy/right-common-carotid-artery/) · [Pericardium](https://durgical.com/en/anatomy/pericardium/) · [Aortic right coronary cusp](https://durgical.com/en/anatomy/right-coronary-leaflet/) · [Left ventricle](https://durgical.com/en/anatomy/left-ventricle/) ## Key points - Paradoxus = inspiratory systolic fall of more than 10 mmHg; tamponade and severe asthma. - Parvus et tardus = severe aortic stenosis. - Bounding with wide pulse pressure = aortic regurgitation. - Alternans = severe left ventricular systolic dysfunction. ## What it is Palpating the carotid or radial assesses amplitude, upstroke and regularity. Some patterns are nearly diagnostic: pulsus paradoxus in tamponade, parvus et tardus in severe aortic stenosis, a bounding pulse in aortic regurgitation and pulsus alternans in severe ventricular failure. ## The anatomy it tests - Paradoxus: on inspiration the right ventricle fills more; if the pericardium prevents expansion, the septum shifts into the left ventricle and stroke volume falls. - Parvus et tardus: the narrowed aortic valve lets blood out slowly and in small volume. - Bounding (water-hammer): large stroke volume and rapid diastolic fall from aortic regurgitation or a hyperdynamic circulation. - Alternans: a very depressed left ventricle alternates strong and weak beats in a regular rhythm. ## How to elicit it - Feel the carotid (one side at a time, mid-neck) for waveform; the radial for rate and rhythm. - Judge amplitude (weak, normal, bounding), upstroke (slow or brisk) and beat-to-beat variation. - Pulsus paradoxus: deflate the cuff slowly; note where sounds are heard only in expiration and where they are heard throughout breathing. - If the difference between them is more than 10 mmHg, pulsus paradoxus is present. - If the rhythm is irregular, count a full minute and compare apical with radial rate (pulse deficit). ## What a positive result means - Paradoxus (inspiratory systolic fall of more than 10 mmHg): cardiac tamponade, severe asthma or COPD exacerbation, massive pulmonary embolism; less often constrictive pericarditis. - Parvus et tardus: severe aortic stenosis. - Bounding with a wide pulse pressure: aortic regurgitation; also anemia, fever, hyperthyroidism, pregnancy, arteriovenous fistula, patent ductus arteriosus. - Alternans: heart failure with severe systolic dysfunction. - Bisferiens (two systolic peaks): aortic regurgitation with or without stenosis, hypertrophic cardiomyopathy. - Irregularly irregular with a pulse deficit: atrial fibrillation. ## Usefulness and limits - Pulsus paradoxus is lost in arrhythmias or extreme hypotension; it may be absent in tamponade with an atrial septal defect or aortic regurgitation. - Waveform is judged better at the carotid than at the radial. ## Test yourself Think of the answer, then tap the question to see it. ## How is pulsus paradoxus defined? As a fall in systolic pressure of more than 10 mmHg during inspiration. ## Which pulse is typical of severe aortic stenosis? Pulsus parvus et tardus: small and slow-rising, best felt at the carotid. ## What does pulsus alternans with a regular rhythm suggest? Heart failure with severe left ventricular systolic dysfunction. ## Why is only one carotid palpated at a time? To avoid reducing blood flow to both sides of the brain and to avoid stimulating the carotid sinus. [Add to my cards (4)](https://durgical.app/estudiar/?add=/en/clinical-exam/abnormal-pulses-paradoxus-alternans-parvus-et-tardus-bounding/) ## See it in 3D The structures of Durgical's 3D anatomy where it is found. - [Radial artery](https://durgical.com/en/anatomy/radial-artery/) - [Common carotid artery](https://durgical.com/en/anatomy/right-common-carotid-artery/) - [Pericardium](https://durgical.com/en/anatomy/pericardium/) - [Aortic right coronary cusp](https://durgical.com/en/anatomy/right-coronary-leaflet/) - [Left ventricle](https://durgical.com/en/anatomy/left-ventricle/) ## Related - [Arterial pulse: rate, rhythm and amplitude](https://durgical.com/en/clinical-exam/arterial-pulse-rate-rhythm-and-amplitude/) - [Cardiac tamponade: Beck triad and pulsus paradoxus](https://durgical.com/en/clinical-exam/cardiac-tamponade-beck-triad-and-pulsus-paradoxus/) - [Valve murmurs: the table to know](https://durgical.com/en/clinical-exam/valve-murmurs-the-table-to-know/) - [Blood pressure measurement](https://durgical.com/en/clinical-exam/blood-pressure-measurement/) - [Peripheral pulses and the ankle–brachial index](https://durgical.com/en/clinical-exam/peripheral-pulses-and-the-ankle-brachial-index/) ## Related conditions - [Cardiac tamponade](https://durgical.com/en/conditions/cardiac-tamponade/) - [Aortic regurgitation](https://durgical.com/en/conditions/aortic-regurgitation/) - [Aortic Valve Stenosis](https://durgical.com/en/conditions/aortic-valve-stenosis/) - [Heart failure](https://durgical.com/en/conditions/heart-failure/) - [Hypertrophic cardiomyopathy](https://durgical.com/en/conditions/hypertrophic-cardiomyopathy/) - [Atrial fibrillation](https://durgical.com/en/conditions/atrial-fibrillation/) - [Chronic obstructive pulmonary disease (COPD)](https://durgical.com/en/conditions/chronic-obstructive-pulmonary-disease/) [← All of the clinical exam](https://durgical.com/en/clinical-exam/) Educational content on the clinical exam; it is learned and practised under supervision. It does not replace assessment by a health professional and is not for self-diagnosis. Sources: [Pulse: MedlinePlus Medical Encyclopedia](https://medlineplus.gov/ency/article/003399.htm) (MedlinePlus, U.S. National Library of Medicine, 2026); [Cardiac tamponade: MedlinePlus Medical Encyclopedia](https://medlineplus.gov/ency/article/000194.htm) (MedlinePlus, U.S. National Library of Medicine, 2026); [Aortic regurgitation: MedlinePlus Medical Encyclopedia](https://medlineplus.gov/ency/article/000179.htm) (MedlinePlus, U.S. National Library of Medicine, 2026); [Aortic stenosis: MedlinePlus Medical Encyclopedia](https://medlineplus.gov/ency/article/000178.htm) (MedlinePlus, U.S. National Library of Medicine, 2026). ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/clinical-exam/abnormal-pulses-paradoxus-alternans-parvus-et-tardus-bounding/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/clinical-exam/abnormal-pulses-paradoxus-alternans-parvus-et-tardus-bounding/