The word(s) "heart" appears 161 time(s) in 147 verse(s) in Quran in Mohsin Khan translation.

(81) Have they not travelled through the land, and have they hearts wherewith to understand and ears wherewith to hear? Verily, it is not the eyes that grow blind, but it is the hearts which are in the breasts that grow blind.

(82) That He (Allah) may make what is thrown in by Shaitan (Satan) a trial for those in whose hearts is a disease (of hypocrisy and disbelief) and whose hearts are hardened. And certainly, the Zalimun (polytheists and wrong-doers) are in an opposition far-off (from the truth against Allah's Messenger and the believers).

(83) And that those who have been given knowledge may know that it (this Qur'an) is the truth from your Lord, so that they may believe therein, and their hearts may submit to it with humility. And verily, Allah is the Guide of those who believe, to the Straight Path.

(84) And those who give that (their charity) which they give (and also do other good deeds) with their hearts full of fear (whether their alms and charities have been accepted or not), because they are sure to return to their Lord (for reckoning).

(85) Nay, but their hearts are covered from (understanding) this (the Qur'an), and they have other (evil) deeds, besides, which they are doing.

(86) It is He Who has created for you (the sense of) hearing (ears), eyes (sight), and hearts (understanding). Little thanks you give.

(87) Men whom neither trade nor sale (business) diverts from the Remembrance of Allah (with heart and tongue), nor from performing As-Salat (Iqamat-as-Salat), nor from giving the Zakat. They fear a Day when hearts and eyes will be overturned (out of the horror of the torment of the Day of Resurrection).

(88) Is there a disease in their hearts? Or do they doubt or fear lest Allah and His Messenger (صلى الله عليه وسلم) should wrong them in judgement. Nay, it is they themselves who are the Zalimun (polytheists, hypocrites and wrong-doers).

(89) And those who disbelieve say: "Why is not the Qur'an revealed to him all at once?" Thus (it is sent down in parts), that We may strengthen your heart thereby. And We have revealed it to you gradually, in stages. (It was revealed to the Prophet صلى الله عليه وسلم in 23 years.).

(90) Except him who brings to Allah a clean heart [clean from Shirk (polytheism) and Nifaq (hypocrisy)]."