Lauren (2011) in “Pediatric Heart Murmurs: Evaluation and management in primary care,” gave an overview of the cardiac assessment, diagnosis of heart murmurs, and referral recommendations among children. Lauren noted that most of the heart murmurs were innocent resulting from a turbulent flow of blood in the pulmonary arteries or due to delayed cardiac development that leads to slight ductus arteriosus in neonates. Pathological heart murmurs result from ventricular septal defect, severe cases of patent ductus arteriosus or congenital heart diseases.
The prevalence rate of heart murmurs among newborns is between 0.6% and 4.2%. About 90% of infants and children experience heart murmurs during infancy. Besides, between 50 and 70% of children are diagnosed with heart murmurs during routine check-ups with less than 1% resulting from congenital heart defects. Of all the reported cases of heart murmurs, 70% are asymptomatic whether innocent or pathological. These statistics indicates that heart murmurs among children are a significant problem.
Heart auscultation normal findings involves a regular pattern of the first sounds (S1) and the second heart sounds (S2). Any other sound (S3 or S4) during the cardiac cycle may indicate a problem. The heart murmur may result from turbulent blood flow, flow from a narrow to dilated blood vessel or heart or regurgitation of the blood into anterior blood chamber due to an incompetent valve. Apart from auscultation, directly observing the precordium may help identify conditions like coarctation.
After examination, the nurse classifies the murmurs based on the timing, intensity, pitch, location, and radiation. The timing of the heart murmurs may be continuous, diastolic, or systolic. Under systolic murmurs, there are holosytolic, early systolic, mid-to-late systolic, and mid-systolic while diastolic are early, mid, and late diastolic. Intensity involves grading the murmur on a scale of 1-6 or 1-4 with 1 indicating barely audible using a stethoscope and 4 or 6 been loud. The pitch is the nature of sound while the location is the part of the chest the nurse hears the murmur.
The nurse can ask the patient about symptoms such as chest pain, syncope, and changes in skin color, palpitation, and activity intolerance. For children, the nurse should ask about the length of gestation, healthy habits, and difficulties in breathing to establish the possible cause of congenital defects. Other indicators of heart murmurs include vital signs like fever, blood pressure, pulse rate and respiratory, oxygen saturation, respiratory efforts, and cyanosis among others.
Moreover, the nurse needs to differentiate common heart murmurs. Innocent murmurs include still, pulmonary, systole murmurs and venous hum. The nurse can hear still murmurs in early systole and have vibratory quality comparable to a rubber band. The systolic flow murmur is high-pitched and located in the superior chest. The pulmonary flow murmur occurs during systole and is audible at the left upper sternal boundary. It is high-pitched and harsh in quality. The venous hum is a typical still murmur with vibratory quality and occurs on the top left and right sternal border and results from blood flowing backwards via the venous system.
Classification of murmur as pathological results from symptoms such as harsh quality of the murmurs, located at the right sternal border (upper), tricuspid location, apex, and pansytolic, continuous, and diastolic murmurs. Patent ductus arteriousus would produce holsytolic and continuous murmur at the upper left sternal border and left side bottom neck section and occurs in premature newborn. A systolic murmur loudest at the upper left sternal border indicates septal defects while systolic murmur in the same location and around the left posterior scapular regions indicate coarctation.
The disruption of the mitral valve and aortic valve would lead to mitral and aortic regurgitation respectively. Although chest X-ray and ECG are of little benefit in diagnosis, the nurse may consider ECG for routine physical examination. An echocardiogram is the most useful method for diagnosis of congenital cardiac malformations. The nurse may refer the patient in case of confusion in the identification of the heart murmurs. Lauren concluded that the nurse is in a position to identify the murmurs early, and should educate the family on the implication on the patient’s health.
Reference
Lauren, W., (2011). Pediatric Heart Murmurs: Evaluation and management in primary care. The Nurse Practitioner Vol. 36 Number 3, page 22-29. Retrieved on March 23, 2016 from http://www.nursingcenter.com/cearticle?tid=1129236
