Heart Sounds Practice: The 5 Places to Listen, S1 to S4, Murmurs and How to Actually Learn Them

Published · By VMS, Alehundred Studios

Heart sounds practice works best in a fixed order: learn the five places to listen, learn what a normal S1 and S2 sound like at each one, then add the extra sounds and the murmurs, and repeat each of them hundreds of times. The repetition is the part most students skip, and it is the part with the strongest evidence: in a controlled study published in Chest, a group of second-year medical students who listened to 500 repetitions of four basic murmurs went from recognizing 13.5% of them to 85%. Below is where to put the stethoscope, what S1, S2, S3 and S4 are, the murmur basics, and a practice plan for medical, PA, nursing and EMS students.

What are the 5 places to listen to heart sounds?

The five classic auscultation areas sit along the sternum and at the apex. A study in Scientific Reports that recorded heart sounds at all five lists them with their landmarks:

  1. Aortic area: "the second intercostal space on the right sternal border"
  2. Pulmonic area: "the second intercostal space on the left sternal border"
  3. Erb's point (also called the secondary aortic area): "the third intercostal space on the left sternal border"
  4. Tricuspid area: "the fourth intercostal space on the left sternal border"
  5. Mitral area (apex): the 5th intercostal space on the midclavicular line, which Stanford Medicine 25 describes as "approximately around the area of the left nipple"

Students remember the order with the mnemonic "APE To Man": Aortic, Pulmonic, Erb's, Tricuspid, Mitral. Go through all five with the diaphragm, then go back through them with the bell, every time, in the same order. A fixed route is what keeps you from skipping a spot when you are nervous in an OSCE.

What are S1, S2, S3 and S4?

S1 and S2 are the two normal heart sounds, the "lub" and the "dub." The National Heart, Lung, and Blood Institute explains both. After the atria fill the ventricles, "the valves between the atria and ventricles close to prevent backflow. The 'lub' is the sound of these valves closing." Then, "After your ventricles contract to pump blood away from the heart, the aortic and pulmonary valves close and make the 'dub' sound."

The gap from S1 to S2 is systole and the gap from S2 to the next S1 is diastole. MedlinePlus puts it simply: "Systole is when the heart is squeezing out blood and diastole is when it is filling up with blood."

S2 has two parts, and that is where the detail lives. Stanford Medicine 25's page on cardiac second sounds explains that S2 is made of aortic valve closure (A2), "which happens first," and pulmonic valve closure (P2), "which happens second." "A2 is heard widely all over the chest," while "Normally, P2 is soft and only heard at the pulmonic region (left parasternal, intercostal space 2)." The split widens when the patient breathes in, because more blood fills the right ventricle and the pulmonic valve closes a little later. To hear it, Stanford's technique is: "Splitting best heard in the 2nd left intercostal space, close to the sternal border," with the diaphragm, and with the patient "semi-recumbent (30-40 degrees upright) and in quiet inspiration."

S3 and S4 are the extra sounds of diastole. A heart sound study in Frontiers in Physiology places S3 just after S2 and notes that "About half of young adults and most children hear it, and it does not necessarily indicate abnormality." S4 comes just before S1. The same review describes it as a sound caused by the contraction of the atria and the filling of the ventricles, "also known as an atrial sound," and one that is difficult to pick up on routine auscultation.

What is a heart murmur, and how do you describe one?

A murmur is the sound of turbulent blood flow. MedlinePlus defines it as "a blowing, whooshing, or rasping sound heard during a heartbeat. The sound is caused by turbulent (rough) blood flow through the heart valves or near the heart."

Not every murmur means disease. "Many heart murmurs are harmless. These types of murmurs are called innocent murmurs." Extra blood flow alone can produce one, for example during exercise, pregnancy, fever, anemia or hyperthyroidism. Timing changes the picture: Stanford Medicine 25 states that "Diastolic murmurs are always a pathological finding on the auscultation of the heart, indicating the presence of a valvular abnormality."

Describe every murmur with the same checklist. MedlinePlus lists what the examiner looks for:

Then grade the loudness. Murmurs are graded on a scale of 1 to 6. "Grade I can barely be heard and is intermittent," and a murmur you can feel with your palm, a thrill, "means the murmur is grade 4 or higher."

Shape matters too. The Scientific Reports authors note that holosystolic murmurs, of uniform intensity through systole, "usually appear in patients with mitral regurgitation (MR), tricuspid regurgitation (TR), or VSD," while crescendo-decrescendo systolic ejection murmurs "are often heard in patients with aortic stenosis (AS), pulmonic stenosis (PS), and atrial septal defect (ASD)."

Position the patient to bring murmurs out. The murmur of mitral stenosis is "heard best using the bell of the stethoscope and with the patient in the left lateral decubitus position," and it presents "as a low-pitched diastolic rumble usually preceded by an opening snap." For aortic regurgitation, Stanford asks the patient "to sit upright on the examination table, lean forward and hold the breath in full expiration."

Why is it so hard to learn heart sounds?

Because recognizing sounds is a perceptual skill, and most students never get enough repetitions. The Chest study opens with a blunt baseline: "The ability of medical students to recognize heart murmurs is poor (20%), and does not improve with subsequent years of training."

Clinical time alone does not fix it. A study of heart and lung auscultation training in BMC Medical Education points out that bedside teaching "is limited by a relatively large student-to-patient ratio, the heterogeneity/variability of clinical presentations, as well as by the inconvenience of repeated physical examinations to patients with advanced disease," and that "clinical practice does not necessarily correlate with skill in auscultation." You may go a whole rotation without hearing a clear aortic stenosis murmur twice.

That is also why this skill is assessed. The AAMC expects every graduating medical student to "Identify, describe, and document abnormal physical exam findings" as part of Core EPA 1.

How do you learn heart sounds? A practice plan that works

You learn heart sounds by focused, repeated listening with immediate feedback, then by applying it on real chests. The evidence points the same way from two angles.

Repetition. In the Chest study, a monitored group listened to 500 repetitions of each of four murmurs and improved from 13.5% to 85%; an unmonitored group did the same on its own and improved from 20.9% to 86.1%. Ten control students went from 24% to 32%, which was not a significant change. The authors concluded: "Five hundred repetitions of four basic cardiac murmurs significantly improved auscultatory proficiency in recognizing basic cardiac murmurs by medical students. These results suggest that cardiac auscultation is, in part, a technical skill."

Structured simulation. In the BMC Medical Education study, fifth-year students who had trained individually for one hour on a patient simulator two years earlier recognized mitral regurgitation 89.7% of the time, against 71.4% for students who had not. The authors found that "training medical students with a patient simulator, individually for one hour, significantly ameliorated their heart auscultation skills over time," and they point to drawing what you hear: "the support of graphic sound display/representation might be beneficial to the acquisition of auscultation skills."

Put together, a week-by-week plan looks like this:

  1. Normal first. Listen to S1 and S2 at all five areas on yourself and on classmates until you can tell them apart at every spot without thinking.
  2. One new sound at a time. Add the S2 split, then S3, then S4, then one systolic and one diastolic murmur. Do not move on until you recognize the current one cold.
  3. Volume over variety. Hundreds of repetitions of a few sounds beat one listen to fifty. Short daily sessions count.
  4. Time every sound. Feel a pulse while you listen so you know which sound is S1 and whether a murmur falls in systole or diastole.
  5. Draw what you hear. Sketch S1, S2 and the murmur shape on a timeline. The BMC authors suggest this is why their students did better on heart sounds than on lung sounds.
  6. Describe it out loud. Location, timing, shape, pitch, grade, radiation, and what changes with position.
  7. Quiz yourself in random order. A heart sounds practice test that shuffles the sounds is closer to a real exam than replaying them in a list.
  8. Then go to real chests. Use the positions that bring sounds out (left lateral decubitus, sitting forward) and compare what you hear with the documented findings.

How do you practice heart and lung sounds together?

Practice them in the same session, because they share the stethoscope, the positions and the same exam station. The BMC Medical Education study tested both, and the lung results show where students struggle. When both groups were tested in their fifth year, wheezes were recognized by about 91% of students and rhonchi by 74 to 75%. Nonmusical sounds were harder: coarse crackles by 67 to 71%, pleural rubs by about 63 to 64%, and fine crackles by only 58 to 63%.

The practical lesson: spend your extra repetitions on fine versus coarse crackles and on pleural rubs, the sounds most often missed. And always listen on bare skin, side to side, comparing one lung field with the same field on the other side.

Where does VMS fit in heart sounds practice?

VMS, the Virtual Medical Simulator, is not a heart-sound library. It trains the encounter around the stethoscope, which is what an OSCE station scores along with your ears. On a PC or in VR, you pick your program (Medicine, Physician Assistant, Nursing or EMS) and run a case as an OSCE station: one virtual patient, a step-by-step checklist and a score from 0 to 100%. You introduce yourself, gain consent, wash your hands or put on gloves, examine the patient with your hands and with tools such as the stethoscope, and close the encounter.

Practice a case in Teach or Train mode, then press the OSCE exam button for a random patient in Test mode, with no hints and a time limit. Every attempt is saved to your account so you can track your scores, and educators see results per student. A good weekly routine pairs both: a sound library for your ear, and VMS so that auscultation sits inside a complete, well-ordered exam. For the full sequence around it, see our guide to physical exam steps.

FAQ

What are the 5 places to listen to heart sounds?

Aortic (2nd intercostal space, right sternal border), pulmonic (2nd intercostal space, left sternal border), Erb's point (3rd intercostal space, left sternal border), tricuspid (4th intercostal space, left sternal border) and mitral (5th intercostal space, midclavicular line, at the apex).

What are normal heart sounds?

S1 ("lub"), the closing of the valves between the atria and ventricles, and S2 ("dub"), the closing of the aortic and pulmonary valves. A split S2 that widens on inspiration is normal, and an S3 can be normal in children and young adults.

How do you learn heart sounds fast?

Pick a few sounds and repeat them hundreds of times with feedback before adding more. In one study, 500 repetitions of four murmurs took students from 13.5% to 85% correct recognition.

How do you practice heart murmurs?

Learn each murmur's timing, location, shape and best position, draw it on a timeline, then test yourself with the sounds in random order. Describe every murmur with the same checklist: timing, location, radiation, shape, pitch and grade.

Is there a heart sounds practice quiz or test format that works?

Yes: a randomized self-test. Shuffle the sounds, name each one, then check the answer right away. Research uses the same format: the BMC study played the sounds in random order, and the Chest study tested students before and after their practice.

Sources

  1. National Heart, Lung, and Blood Institute. How the Heart Works: How the Heart Beats. NIH, 2025.
  2. MedlinePlus, National Library of Medicine. Heart murmurs. 2026.
  3. Association of American Medical Colleges. Core Entrustable Professional Activities for Entering Residency: Curriculum Developers' Guide. AAMC, 2014.
  4. Stanford Medicine 25. Cardiac Second Sounds. Stanford Medicine.
  5. Stanford Medicine 25. Approach to the Exam for Diastolic Murmurs. Stanford Medicine.
  6. Wang JK, Chang YF, Tsai KH, et al. Automatic recognition of murmurs of ventricular septal defect using convolutional recurrent neural networks with temporal attentive pooling. Scientific Reports, 2020.
  7. Li F, Zhang Z, Wang L, et al. Heart sound classification based on improved mel-frequency spectral coefficients and deep residual learning. Frontiers in Physiology, 2022.
  8. Barrett MJ, Lacey CS, Sekara AE, Linden EA, Gracely EJ. Mastering cardiac murmurs: the power of repetition. Chest, 2004.
  9. Bernardi S, Giudici F, Leone MF, et al. A prospective study on the efficacy of patient simulation in heart and lung auscultation. BMC Medical Education, 2019.