The terms Lubb and Dubb relate to which one of the following?

The terms 'Lubb' and 'Dubb' (often written as lub-dub) refer to the normal heart sounds heard during cardiac auscultation. These sounds are produced by the rhythmic opening and closing of the heart valves during the cardiac cycle [t1]. The first heart sound (S1), or 'lubb', is primarily caused by the closure of the atrioventricular valves (mitral and tricuspid) at the beginning of ventricular systole [t1][t3]. The second heart sound (S2), or 'dubb', is a diastolic sound caused by the closure of the semilunar valves (aortic and pulmonary) at the end of ventricular systole [t1][t3]. These sounds are essential clinical indicators used by medical professionals to evaluate cardiac health and detect abnormalities like murmurs or gallops [t1][t5]. In contrast, lung sounds are characterized by terms like wheezing or crackling [t2], and dental or ocular functions do not produce these specific rhythmic acoustic patterns.

Sources

1. [1] https://www.ncbi.nlm.nih.gov/books/NBK541010/